JP2003151845A - Manufacturing method of laminated ceramic electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated ceramic electronic component wherein troubles such as warp hardly occur regardless of the multilayering and thinning of a ceramic green sheet. SOLUTION: If an inorganic compound powder particle CP with an average grain diameter of 500 nm or less is contained, the baking contraction of a wiring pattern layer 6 can be delayed properly when the ceramic green sheet 5 is formed to a laminated body and baked. As a result, the generation of the warp or the like can be restrained effectively. Furthermore, since the laminated green sheet 5 is laminated after a via hole formed in each ceramic green sheet 5 is charged with first conductor powder, it is possible to raise the charging density of the first conductor powder in each via hole 4 of the ceramic green sheet 5 and further to raise the density of a via electrode obtained after baking, thus raising the conductivity of a via electrode.

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 suitable for use as, for example, a monolithic capacitor, a monolithic inductor, a monolithic capacitor-embedded substrate, a monolithic module substrate, or the like.

[0002]

2. Description of the Related Art In the above-mentioned laminated ceramic electronic component (for example, laminated ceramic capacitor), a laminated green body in which ceramic green sheets and wiring pattern layers are alternately laminated is conventionally prepared, and the laminated ceramic green body is manufactured. It is manufactured by co-firing.

[0003]

By the way, when the ceramic green sheet and the wiring pattern layer are to be simultaneously fired in the form of a laminate, the firing temperature is naturally set to a temperature range in which the firing of the ceramic sufficiently proceeds. To be done. On the other hand,
The wiring pattern layer is formed of metal powder, and the metal powder usually starts firing in a temperature range lower than that of ceramic.
That is, when the laminated body is fired, there is a difference in firing temperature range between the ceramic green sheet and the wiring pattern layer. Therefore, firing of the wiring pattern layer mainly composed of metal is more preferable than firing of the ceramic green sheet. Always tends to stay ahead.

The wiring pattern layer largely shrinks in the in-plane direction when firing is started. On the other hand, since the ceramic green sheet has not reached the firing temperature range, shrinkage has not progressed yet. Due to this difference in shrinkage,
As shown in FIG. 13, the unshrinkable ceramic green sheet 5 is easily pulled by the wiring pattern layer 6 to cause a warp. As a result, there is a problem that defects such as unevenness and bending are likely to occur on the surface of the obtained component. As the firing of the ceramic green sheet 5 progresses, such warpage is reduced to some extent, but some residual is inevitable.

Today, laminated electronic components are required to have higher performance, higher integration, and smaller size (thinner).
Increasing the number of laminated sheets and making them thinner are being further promoted. As the number of laminated sheets increases, the influence of uneven shrinkage as described above is more likely to occur, and the thinner ceramic green sheet is also weighted, so that problems such as warpage are more likely to occur in laminated components after firing. This tendency is particularly remarkable in the case of a monolithic ceramic capacitor in which electrodes having a large area are formed as wiring portions. Then, in order to prevent the occurrence of such warp, it is necessary to control each step in manufacturing with high accuracy, and also the burden of quality inspection of parts after firing, the yield decrease due to the rejection of rejected products, etc. Therefore, the manufacturing cost is likely to increase, which is an obstacle to cost reduction.

In the present invention, in a multilayer ceramic electronic component that is required to have high performance and thinness, defects such as warpage are reduced, quality is improved and cost is reduced regardless of the multilayered and thinned ceramic green sheets. It is a direct challenge to

[0007]

Means for Solving the Problems and Effects of the Invention In order to solve the above problems, the first method of manufacturing a laminated ceramic electronic component according to the present invention is the first ceramic green sheet for base portion and the second ceramic green sheet for base portion. A via hole formed by alternately laminating a plurality of laminating ceramic green sheets and a wiring pattern layer between the base ceramic green sheet and a laminating portion of two or more laminating ceramic green sheets. A step of producing a laminated green body in which at least one of a plurality of laminated wiring pattern layers and a via electrode which becomes electrically conductive after firing are formed; and a step of firing the laminated green body. And a second conductor powder that forms a wiring pattern layer contains a metal powder and an inorganic compound powder having an average particle diameter of 500 nm or less. , The first conductor powder forming the via electrode does not contain the inorganic compound powder or the content thereof is lower than that of the second conductor powder, and further, in the step of producing the laminated green body, the ceramic green for lamination is formed. After filling the first conductor powder into the via holes formed in the sheet to form a filled ceramic green sheet for lamination, either the first ceramic green sheet for the base portion or the second ceramic green sheet for the base portion It is characterized in that a filled ceramic green sheet for lamination is laminated on the main surface thereof.

Similarly, a plurality of laminated ceramic green sheets and wiring pattern layers are alternately laminated between the first base portion ceramic green sheet and the second base portion ceramic green sheet. In the via hole formed so as to penetrate the laminated portion of the two or more laminated ceramic green sheets, at least one of the laminated wiring pattern layers is electrically connected after firing. The second conductor powder forming the wiring pattern layer includes a metal powder and an average particle diameter of 500 nm or less including a step of producing a laminated green body having a via electrode formed thereon and a step of firing the laminated green body. The first conductor powder which contains the inorganic compound powder and further forms the via electrode does not contain the inorganic compound powder or is different from the second conductor powder. Also lower the content thereof, additionally, in the step of preparing a laminated green body, the first base portion for ceramic green sheets and one of the main surfaces on ceramic green sheets for the second base portion,
Alternately repeating a step of laminating a laminated ceramic green sheet in a state where the first conductor powder is not filled in the via hole and a filling of the via hole of the laminated ceramic green sheet with the first conductor powder. Is characterized by.

In the present specification, the names of "via electrode" and "wiring pattern layer" (and their subordinate concepts) are used in common for both the state before firing and the state after firing for convenience.
Further, in the present specification, the “main component” means that the weight content of the component is higher than the total weight content of the other components, and “two or more components are the main components”. "
Means that the total of these components is higher than the total of the weight content of the other components. Further, the average particle size of the inorganic compound particles is the parallel line distance d1 of the minimum interval and the parallel line distance d2 of the maximum interval circumscribing the particle outline of the primary particles observed in the scanning electron microscope observation image of the tissue section. When the arithmetic mean value of and is defined as the particle size, it means the average value.

In the above method of the present invention, the second powder for the wiring pattern layer is, for example, as shown in FIG. 14, conductive powder particles made of metal powder or the like (hereinafter referred to as a metal powder, referred to as a second metal). (Referred to as powder): If it is composed only of 310, at a firing temperature compatible with ceramics, shrinkage rapidly progresses due to diffusion between metal powder particles and melting of the particles, resulting in warpage as shown in FIG. Leads to. However, as shown in FIG. 15, when the inorganic compound powder particles 315 having the above-mentioned particle size are contained, the inorganic compound powder particles 315 are separated between the metal powder particles 310 when the ceramic green sheet is fired as a laminated body. By inhibiting the diffusion and also helping the inorganic compound powder particles 315 to eliminate the spatial occupation of the metal powder particles 310, the firing shrinkage of the wiring pattern layer can be delayed appropriately.
As a result, it is possible to effectively suppress the occurrence of the above-mentioned warpage and the like. According to the above manufacturing method, the via electrode is
The portion located in the dielectric ceramic layer between the wiring pattern layers connected by the via electrode is formed so that at least the inorganic compound powder is not contained or the content of the inorganic compound powder is lower than that of the wiring pattern layer. . As a result, the conductivity of the via electrode is significantly improved.

In the first method, the first conductor powder is filled in the via holes formed in the individual ceramic green sheets for lamination, and then the layers are laminated. In the method, in the step of manufacturing the laminated green body, the first
By alternately repeating the step of laminating the ceramic green sheets for lamination without being filled with the conductor powder and the filling of the via holes of the laminated ceramic green sheets with the first conductor powder, the ceramic for lamination is laminated. The packing density of the first conductor powder in each via hole of the green sheet can be increased. As a result, the density of the via electrode obtained after firing becomes high, which contributes to increase the conductivity of the via electrode.

In this case, it is desirable to press the laminated body of the filled ceramic green sheets for lamination in the laminating direction in order to enhance the pressure bonding state of the ceramic green sheets and obtain a fired body with few defects. The pressing may be performed after all the filled ceramic green sheets for lamination are laminated, but every time one layer of the laminated ceramic green sheets for filling is laminated, the laminated ceramic green sheets for lamination are laminated. If is pressed in the stacking direction, the pressure-bonded state of the ceramic green sheet can be further enhanced.

In the present invention, specifically, a part of the via electrode is formed on at least one surface of the first base ceramic green sheet and the second base ceramic green sheet. It is possible to manufacture a monolithic ceramic electronic component as a surface mount type component by connecting it to a flip chip type surface mount terminal. Electronics,
Especially in communication devices such as mobile phones and communication boards, there has been a significant tendency toward downsizing in recent years, and it is possible to save the mounting space on the board and to mount the components simply by reflowing the solder after mounting the components. The adoption of surface mount type components is advancing rapidly. In the case of small flip-chip type surface mount type components, even slight warpage or unevenness of parts greatly influences factors that control the bonding accuracy of the terminals, such as the coplanarity of the flip chip type surface mount terminals that are formed.
There is a problem that is directly linked to defects. Therefore, by applying the manufacturing method of the present invention, it is possible to effectively reduce the warpage and the like of such flip-chip type surface mount type components, and to significantly reduce the defect rate even when the miniaturization is promoted. This contributes to the improvement of yield. In addition, as described above, the via electrode connecting the capacitor electrode is such that at least the portion located in the dielectric ceramic layer does not contain the inorganic compound powder or the content of the inorganic compound powder is lower than that of the wiring pattern layer. Because it is formed
The conductivity is significantly improved, which is also advantageous in reducing the parasitic inductance of the capacitor. The effect is particularly remarkable when the present invention is applied to a capacitor for high frequency (for example, a frequency of 1 GHz or more).

For example, the surface mount type component can be manufactured as a surface mount type multilayer ceramic capacitor as follows. That is, the first and second wiring pattern layers face each other with the ceramic green sheet for lamination interposed therebetween.
Including a capacitor electrode, the via electrode is electrically conductive with the first capacitor electrode and is not electrically conductive with the second capacitor electrode, and the via electrode is electrically conductive with the second capacitor electrode. The second conductive type via electrode which is not conductive with the first capacitor electrode is formed. Then, the flip-chip type surface mounting terminal is formed so as to be selectively conducted to either the first conduction type via electrode or the second conduction type via electrode. In a monolithic ceramic capacitor, the capacitor electrodes forming the wiring pattern layer have a relatively large area, and moreover, a large number of capacitor electrodes are stacked in the layer thickness direction. It is easy and the above-mentioned trouble is more likely to occur. Therefore, the ripple effect by the application of the present invention is particularly large.

The second powder used for forming the wiring pattern layer preferably has an average particle size of the metal powder (hereinafter referred to as the second metal powder) contained therein of 0.1 to 3 μm. Thereby, the inorganic compound powder to be blended with the second powder,
That is, in combination with setting the average particle diameter of the inorganic compound particles in the wiring pattern layer after firing to 500 nm or less, the effect of suppressing the firing shrinkage of the metal powder by the inorganic compound powder can be uniformly expressed over the entire layer. Therefore, the occurrence of warpage can be suppressed more effectively. The reason why the average particle size of the inorganic compound powder is 500 nm or less is that the firing shrinkage of the metal powder particles can be effectively suppressed by the inorganic compound powder in order to effectively prevent the problems such as the warp. When the average particle size of the inorganic compound powder exceeds 500 nm, the number of particles of the inorganic compound powder is small, so that the effect of suppressing firing shrinkage is impaired and the warp preventing effect cannot be sufficiently achieved. Further, if it is larger than the second metal powder, a uniform dispersibility cannot be obtained, and thus a sufficient effect of suppressing firing shrinkage cannot be obtained. On the other hand, the lower limit of the average particle size of the inorganic compound powder is not particularly limited, but the extremely small particle size powder easily causes agglomeration,
There may be a limit to achieving uniform dispersion, and price increases are likely to occur. Considering these points, it is desirable to set the average particle diameter of the inorganic compound powder to, for example, about 5 nm as a guideline for the lower limit value.

The average particle size of the second metal powder is 0.1 to 3 μm.
The reason is that even a thin wiring pattern layer having a thickness of several μm or less can be formed uniformly. When the average particle diameter of the second metal powder exceeds 3 μm, the surface roughness deteriorates,
Increased resistance in thin wires, increased impedance due to skin effect in high frequency range (and increased transmission loss of high frequency signals), and poor conduction. In addition, in thin ceramic layers, decrease in withstand voltage etc. or worst case , A short circuit failure due to penetration occurs. When the average particle size is 0.1 μm or less, not only the shrinkage amount during firing increases, but also the handling property becomes poor and the cost disadvantageous.

The inorganic compound powder contained in the second powder is
The average particle size is preferably 100 nm or less, and more preferably 50 nm or less, which is more convenient for uniformly exhibiting the shrinkage suppressing effect of the wiring pattern layer and preventing defects such as warpage. In addition, it is desirable that the inorganic compound powder contained in the second powder has a blending ratio in the second powder adjusted to, for example, 0.5 to 30 mass%. If the blending ratio is less than 0.5% by mass, the effect of suppressing the shrinkage of the wiring pattern layer will be insufficient, and if it exceeds 30% by mass, the electrical conductivity of the obtained wiring pattern layer will not be sufficiently secured.

Next, it is necessary to increase the average particle size of the conductive powder (hereinafter referred to as a first metal powder, represented by a metal powder) in the first powder forming the via electrode to 2 to 20 μm. This is because the filling rate in the interior is increased and it is easy to form a dense and highly conductive via electrode. If the average particle size of the first metal powder is less than 2 μm, the powder packing density in the via electrode is insufficient, and a dense via electrode cannot be obtained, or
Due to excessive contraction, the via electrode may be separated from the inner peripheral surface of the via hole. On the other hand, when the average particle diameter of the first metal powder exceeds 20 μm, the sinterability is impaired, which leads to a problem that a dense via electrode cannot be obtained. The average particle size of the first metal powder is more preferably adjusted in the range of 5 to 10 μm.

Since the via electrode is less likely to cause a mismatch in firing shrinkage timing than the wiring pattern layer, it is not necessary to consider firing shrinkage control as much as the wiring pattern layer. Therefore, in order to obtain as high a conductivity as possible, the first powder to be used has a lower content of the inorganic compound powder than the second powder, or does not contain the inorganic compound powder. Is good.

Dielectric constituting ceramic green sheet
As a good example of the body ceramics, the alumina content is 98
% Or more of alumina ceramics and mullite ceramics
Mix, aluminum nitride ceramics, silicon nitride ceramic
Ramix, silicon carbide ceramics and glass ceramics
Materials with low dielectric loss even in high frequencies such as
Are preferably used in the present invention. Especially with low resistance and high frequency
Conductor of low melting point metal such as Cu and Ag, which has less signal loss
Glass and non-glass ceramics can be used in layers.
Composite material with Mick filler (hereinafter referred to as glass ceramic
Mick) is preferred. Also, high frequency
High purity in terms of low dielectric loss in waves
It is desirable to use aluminous ceramics.
The other dielectric ceramic layers are made of ferroelectric materials.
Perovskite oxides can be used. This is AT
iO_ThreeRepresented by the chemical formula (A: alkaline earth metal element)
The site of A is replaced with Ba, which is an alkaline earth metal element.
Or Ba and one or two of Mg, Ca, and Sr.
More than one kind, and further the above ATiO _Three
Part of the Ti site of was replaced with Zr or Hf
Or PbTiO _ThreeOr PbTiO_ThreeAnd P
bZrO_ThreePZT or KNb which is a solid solution with
O_ThreeAnd so on. Such a ferroelectric acid
As the compound, the composition ratio became more stable as the number of constituent elements decreased.
In this state, the crystals are dispersed and formed in the packed bed, resulting in stable crystals.
The function of forming, and by extension, improving the dielectric constant, is further enhanced.
It is thought to be done. Furthermore, the dielectric constant near room temperature
And in consideration of environment, especially BaTiO 3._ThreeIs preferred
is there.

It is necessary to select the above-mentioned material of the metal powder for forming the wiring pattern layer and the via electrode in consideration of the simultaneous sinterability with the ceramics, and in particular, the simultaneous sinterability with the ceramics is taken into consideration. When doing, Ag, Au,
It is desirable to use a material containing one or more selected from Ni, Cu, Pt and Pd as a main component.

Next, as the first inorganic compound powder contained in the second powder, one made of at least one of aluminum oxide, silicon dioxide and titanium oxide can be particularly preferably used.

On the other hand, the inorganic compound powder blended in the second powder may contain a second inorganic compound powder made of a dielectric ceramic powder that constitutes a ceramic green sheet. By using such a second inorganic compound,
The coefficient of linear expansion of the dielectric ceramic layer and the wiring pattern layer after firing can be made close to each other, and the effect of suppressing delamination between the dielectric ceramic layer and the wiring pattern layer, etc., especially when cooling after firing is also included. can get. For example, when the dielectric ceramic contains a ferroelectric perovskite type oxide, the second inorganic compound powder contains a ferroelectric perovskite type oxide powder, whereby the above effect is further improved. It can be salient.

The inorganic compound powder is a first powder composed of at least one of aluminum oxide, silicon dioxide and titanium oxide.
Of the inorganic compound powder and the second inorganic compound powder, which is the ceramic powder forming the ceramic green sheet,
It suffices that it is configured to include at least one, and both can be used alone or both can be used in combination. As the first inorganic compound powder, one having an average particle size smaller than that of the second inorganic compound powder can be used. As the second inorganic compound powder uses the dielectric ceramic powder that constitutes the ceramic green sheet as described above, the lower limit of the average particle size cannot be reduced so much in consideration of the productivity of the ceramic green sheet. However, there is no such limitation on the first inorganic compound powder, and by using a powder having a smaller particle size than the second inorganic compound powder, the dispersion effect in the wiring pattern layer, and thus the firing shrinkage suppression effect described above. Can be further enhanced.

Next, in the above-mentioned ceramic green sheet, a wiring pattern layer is formed on the first main surface, and the second main surface facing the first main surface is covered with a peelable resin film. Can be

The resin film as described above is attached to the resin film by diverting the carrier film used for forming the ceramic green sheet (for example, the carrier film formed by the doctor blade method). Ceramic green sheets can be easily manufactured. In this case, it is more efficient if the via hole is formed so as to penetrate the ceramic green sheet together with the resin film.

Particularly when a thin ceramic green sheet is used, if the resin film is formed thicker than the ceramic green sheet, the handling effect of the ceramic green sheet is more remarkable. As an example,
When the thickness of the ceramic green sheet is 1 to 25 μm, the thickness of the resin film is preferably adjusted to 15 to 80 μm. When the thickness of the resin film is less than 15 μm, the handling improvement effect of the ceramic green sheet with a resin film becomes insufficient, and when the thickness exceeds 80 μm, the handling improvement effect is saturated and waste of material increases, and The rigidity becomes high, and when peeled off from the ceramic green sheet, a problem may occur in that a part of the ceramic green sheet is scooped out in the form of being attached to the resin film. The thickness of the resin film is more preferably adjusted in the range of 20 to 50 μm.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to the examples shown in the drawings. FIG. 7 shows a cross-sectional structure of a surface mount type multilayer ceramic capacitor (hereinafter, also simply referred to as a capacitor) 40 which is an example of a multilayer ceramic electronic component to which the present invention is applied. In the capacitor 40, the dielectric ceramic layers 5 and the wiring pattern layers 6 are alternately laminated, and the wiring pattern layers 6 facing each other across the dielectric ceramic layers 5 penetrate the dielectric ceramic layers 5. , 8 ′ has a structure electrically connected. The wiring pattern layer 6 includes first and second capacitor electrodes 6a and 6b facing each other with the dielectric ceramic layer 5 in between, and the via electrodes 8 and 8'are electrically connected to the first capacitor electrode 6a. A first conductive type via electrode 8 that does not conduct with the second capacitor electrode 6b;
Second conductive type via electrode 8'which is electrically conductive with the capacitor electrode 6b and is not conductive with the first capacitor electrode 6a. Then, the flip chip type surface mount terminal 31 selectively conducting to each of the first conductive type via electrode 8 and the second conductive type via electrode 8 ′ is connected to the capacitor 40.
The metal bumps 32 are formed on the main surface on one side of each of the above, and are provided with metal bumps 32 for surface mounting.

The via electrodes 8 and 8'and the wiring pattern layer 6 are made of Ag, AgPt, AgPd, Au, Ni and Cu.
It is composed of a metal. As shown in FIGS. 9 to 11, the wiring pattern layer 6 has an average particle size of 500 nm or less (preferably 100 nm or less, more preferably 50 n or less).
(m or less) inorganic compound particles 317 or 316 have a structure in which they are dispersed in a metal phase 313 made of the above metal. On the other hand, in FIG. 7, a portion (hereinafter, also referred to as a main portion) 8a of the via electrode 8 or 8 ′ located in the dielectric ceramic layer 5 between the wiring pattern layers 6 connected by the via electrode 8 or 8 ′. Has a structure composed of only a metal phase containing no inorganic compound particles. Since the wiring pattern layer 6 has a structure in which inorganic compound particles having an average particle diameter of 500 nm or less are dispersed in the metal phase, high-quality surface mount type multilayer ceramic capacitor 4 in which defects such as warpage are reduced
0 is realized. On the other hand, the via electrodes 8 and 8'include the main part 8
Since a is formed so as not to contain the inorganic compound powder, the conductivity is greatly improved, and thus the capacitor 40
It is effective in reducing the parasitic inductance.

An example of the manufacturing process of the capacitor 40 according to the present invention will be described below. The capacitor 40 is manufactured using a ceramic green sheet. The ceramic green sheet can be manufactured by the following doctor blade method. First, a raw material ceramic powder made of a dielectric ceramic (for example, in the case of glass ceramic powder, borosilicate glass powder and BaTiO ₃
Powder mixed with ceramic filler powder such as: average particle diameter of 0.3 to 1 μm) in a solvent (acetone, methyl ethyl ketone, diacetone, methyl isobutyl ketone, benzene, bromochloromethane, ethanol, butanol, propanol, toluene, xylene, etc.) ), Binder (acrylic resin (eg, polyacrylic acid ester, polymethyl methacrylate), cellulose acetate butyrate, polyethylene, polyvinyl alcohol, polyvinyl butyral, etc.), plasticizer (butylbenzyl phthalate, dibutyl phthalate, dimethyl phthalate, phthalate) Acid ester, polyethylene glycol derivative, tricresole phosphate, etc., peptizer (fatty acid (glycerin trioleate, etc.), surfactant (benzene sulfonic acid, etc.), wetting agent ( Le Kill allyl polyether alcohols, spot ethylene glycol ethyl ether, Nitinol Le phenyl glycol, polyoxyethylene esters, etc.) were kneaded by blending additives such as, making a slurry.

As shown in FIG. 8, the open bottom of the container 301 is closed with a carrier film 302 made of a resin film such as polyethylene terephthalate, and the above-mentioned slurry 303 is filled in the container 301. Carrier film 3
02 can be delivered to the container 301 in the longitudinal direction in the plane at a predetermined speed, while a doctor blade 304 is disposed on the side wall portion of the container 301 on the front side in the delivery direction, and its lower edge and the carrier film 302. A certain amount of gap 305 is formed between and. When the delivery of the carrier film 302 is started in this state, the slurry coating layer 306 is formed on the carrier film 302 by the doctor blade 304 so as to be scraped to a thickness corresponding to the gap 305. Then, a drying chamber 307 is arranged on the downstream side in the delivery direction, and the slurry coating layer 306 on the carrier film 302 is exposed to the warm air 308 flowing in the chamber 307 to evaporate the solvent, and thus the ceramics. It becomes a green sheet 309. As is apparent from this step, the ceramic green sheet 309 is obtained in the form of a continuous strip in which the carrier film 302 is integrated on the main surface on one side, and cut into an appropriate size.
Used for manufacturing laminated electronic components.

In this embodiment, the ceramic green sheet 309 has a thickness of 3 to 25 μm, and the carrier film 302 (resin film) has a thickness of 30 to 50 μm.
It is supposed to be m.

Next, a first powder printing paste for forming a via electrode (hereinafter referred to as a via electrode paste) is prepared. As shown in FIG. 12, the metal powder 312 used is
For example, Ag, AgPt, AgPd, Au, Ni and Cu
The average particle size is adjusted in the range of 2 to 20 μm. In this metal powder 312,
A via electrode paste is obtained by mixing and adjusting an organic solvent such as butyl carbitol so that an appropriate viscosity is obtained. In the present embodiment, Ag, AgPd, AgP
t was used.

On the other hand, a second powder printing paste (hereinafter referred to as a wiring pattern layer paste) for forming a wiring pattern layer is prepared. As shown in FIGS. 9 to 11, the metal powder 311 used has the same material as that of the metal powder 312, for example, but has an average particle size adjusted to a small value of 0.1 to 3 μm. This metal powder 311 has an average particle size of 500
nm (preferably 100 nm or less, more preferably 50 nm or less) of an inorganic compound powder is blended in the range of 0.5 to 30% by weight, and an organic binder such as ethyl cellulose and an organic solvent such as butyl carbitol are further added. By forming and adjusting so that an appropriate viscosity can be obtained, a wiring pattern layer-forming material can be obtained.

As the inorganic compound powder, as shown in FIG. 9, the raw material ceramic powder of the ceramic green sheet 309 may be used as the second type inorganic compound powder 316,
As shown in FIG. 10, together with the second type inorganic compound powder 316, the first type inorganic compound powder made of at least one of aluminum oxide (Al ₂ O ₃ ), silicon dioxide (SiO ₂ ) and titanium oxide (TiO ₂ ). (Average particle size 100n
m or less, preferably 50 nm or less) 317 may be blended and used. Further, as shown in FIG. 11, the first type inorganic compound powder 317 may be used alone. All of these inorganic compound powders are metal powders 3 during firing.
11 shrinks and the metal matrix 31 of the wiring pattern layer
When it becomes 3, it has a function of suppressing the firing shrinkage. Particularly excellent in this firing suppression effect is the embodiment of FIG. 11 in which the first-type inorganic compound powder 317 is used alone, and the embodiment of FIG. 10 in which it is used in combination with the second-type inorganic compound powder 316.

Using the ceramic green sheet 309 and the metal paste, the capacitor 40 can be manufactured as follows. (Hereinafter, in order to facilitate the explanation, the reference numerals and names of the parts before firing are the same as those after firing. The reference numerals or names of the respective parts of the capacitor 40 are used instead. Figure 1
Shows an outline of the process. As shown in (a), a second base ceramic green sheet 21 is prepared, and a lamination ceramic green sheet 5 thinner than the second ceramic green sheet 21 is separately prepared. Multiple via holes 4
Are formed in the same position, and the via electrode 8 is formed by filling each via hole 4 with a via electrode paste. Further, on one surface of the ceramic green sheet 5, an internal electrode 6 (hereinafter referred to as a first and a second capacitor electrode 6a, which is a wiring pattern layer) is formed so as to be electrically connected to each via electrode 8.
6b) is used as a generic name) and is formed by printing using a wiring pattern layer paste. Next, (b)
As shown in FIG. 3, these laminated ceramic green sheets 5 are sequentially laminated on the second base ceramic green sheet 21. Then, as shown in (c), the first base portion ceramic green sheets 1 in which the via electrodes 3 are formed in the via holes 2 are overlapped and pressure-bonded, and a predetermined number N of ceramic green sheets finally required. 5
A laminated green body 30 is produced by alternately laminating (the ceramic green sheets 1 and 21 for the base portion are added thereto) and a predetermined number of wiring pattern layers. afterwards,
As shown in (d), a pattern of the mounting pad 31 is formed on the via electrode 3 formed on the base ceramic green sheet 1, and a metal bump 32 is formed on the pad 31 after firing the laminated green body 30. By forming, the surface mount type multilayer ceramic capacitor 40 is obtained.

FIG. 2 is a diagram showing in more detail the manufacturing process of the first ceramic green sheet 1 for the base portion. Ceramic green sheet 30 obtained by the method of FIG.
9 is cut together with the carrier film 302 into a predetermined length.
As shown in (1), the cut carrier film 302 becomes the back tape 11, and the ceramic green sheet 1 integrated with the back tape 11 is obtained. The ceramic green sheet 1 has a thickness equal to or greater than that of the laminated ceramic green sheet 5 (for example, about 2 to 10 times as thick). Next, as shown in (2), the base tape ceramic green sheet 1 with the back tape is attached to the mold,
A plurality of via holes 2 are formed in a predetermined pattern by numerically controlled punching means or via forming means such as a laser drilling device. Furthermore, in (3), the via hole 2
Then, the via electrode 3 is formed by filling and solidifying the above-mentioned via electrode paste by, for example, hole filling printing. The second base green ceramic sheet 21 is manufactured in the same manner as the first base green ceramic sheet 1 except that the via holes are not punched and the via electrodes are not filled.

Further, as shown in FIG. 3A, a ceramic green sheet 5 for lamination is prepared. This has a back tape (carrier film) 11 similar to that described above and is formed to be thinner than the base sheet.
Further, as shown in FIG. 3B, the via hole 4 is formed at a predetermined position of the laminated ceramic green sheet 5 by the above-mentioned via forming means. Next, as shown in (3), the via electrode 8 is formed by filling the via electrode paste into the via hole 4 by, for example, hole filling printing. Then, as shown in (4), the above-mentioned wiring pattern layer paste is applied to the sheet surface (main surface) on the side opposite to the back tape 11 of the ceramic green sheet 5 in which the via holes 4 are opened by, for example, screen printing. By applying in a predetermined pattern, the internal electrode 6 (first capacitor electrode 6a) having a predetermined pattern is formed.

Similarly, as shown in (5) to (6), the via hole 4 is filled with the conductive paste in another ceramic green sheet 5 for lamination to form the via electrode 8.
Further, the internal electrode 6 (first electrode) is arranged in an arrangement pattern different from that of (4).
To form the capacitor electrode 6b). That is, the first ceramic green sheet 5 with a via electrode that holds the internal electrodes 6 in the first arrangement pattern with respect to the sheet ((4) in FIG. 3) and the internal electrodes 6 with the second arrangement pattern in the sheet are held. Then, the second ceramic green sheet 5 with a via electrode ((6) in FIG. 3) is prepared.

By alternately stacking these two types, the ceramic green sheets 5 and the internal electrodes 6 can be alternately stacked. Here, the ceramic green sheet 1 functions as a dielectric to be interposed between the internal electrodes 6 and separates two types of internal electrodes (that is, the first and second capacitor electrodes 6a and 6b) for each type. It plays the role of a holding body or a holding body that holds (carries) separately.

Then, as shown in FIG. 4, the laminated ceramic green sheet 5 having the via electrode 8 formed therein and the internal electrode 6 formed on the sheet surface on the side opposite to the back tape 11 is formed into a second ceramic green sheet. A plurality of layers are laminated on the ceramic green sheet 21 that serves as the base portion. More specifically, the ceramic green sheet 2 serving as the second base portion
The ceramic green sheet 5 so that the internal electrode 6 formed on one surface of the laminating ceramic green sheet 5 faces the sheet surface opposite to the back tape 11 of FIG.
Are stacked, and pressure is applied in the stacking direction for pressure bonding. Next, the back tape 11 of the pressure-bonded ceramic green sheet 5 is peeled off, and the next ceramic green sheet 5 is placed on the sheet surface after the peeling so that the internal electrodes 6 formed on one side of the ceramic green sheet 5 face each other. And crimp in the same way.

In the same manner, the ceramic green sheets 5 are sequentially crimped so that the internal electrodes 6 are alternately sandwiched and laminated (see FIG. 5), and when the planned number of layers is reached, FIG. 6 is obtained. As shown, the laminated green body 30 is obtained by laminating and pressure-bonding the ceramic green sheets 1 which are the first base portions. The ceramic green sheet 5 and the ceramic green sheet 1 are
It is also possible to first stack them all together and then apply pressure in the stacking direction, but by applying pressure for each layer to perform pressure bonding as described above, the pressure history in the layer thickness direction can be made uniform and there are few defects. This is advantageous in obtaining the laminated green body 30. The via electrodes 8 (also referred to as via electrode forming conductive portions) of the plurality of ceramic green sheets 5 stacked in this manner are connected to each other in the thickness direction (stacking direction) of the stacked green body 30 and an appropriate number of them are formed. Connecting (collective) via electrodes, and these via electrodes are also electrically connected to the via electrodes 3 of the ceramic green sheet that is the first base portion,
The via electrodes 8 and 8 ′ are exposed on the main surface of one side of the laminated green body 30. These can be generally divided into two groups, specifically, positive and negative electrode groups of capacitors. One of them is the first conductive type via electrode 8 and the other is the second conductive type via electrode 8 ′. As shown in FIG. 6, the internal electrodes 6 (capacitor electrodes 6a and 6b) that are electrically connected to the via electrodes 8 and 8'are partially opposed to each other in an insulating form with the ceramic green sheet 5 interposed therebetween, thereby forming a capacitor structure. Is formed.

In FIG. 6, a mounting pad 31 for later forming metal bumps is provided on a further exposed via electrode 3 with a predetermined conductive paste, for example, a conductive paste similar to the above-mentioned via electrode and internal electrode. Is printed by screen printing or the like. After cutting such a laminated green body 30 into a predetermined green chip shape as necessary,
This is degreased and fired at a predetermined temperature and atmosphere to obtain a laminated fired body 40 of the laminated ceramic capacitor shown in FIG.
After firing, necessary metal bumps 32, for example, solder bumps are formed on the pads 31 of the laminated fired body 40 to form a laminated ceramic capacitor chip (component).

At the time of this firing, the wiring pattern layer paste for forming the internal electrodes 6 (wiring pattern layer) contains the above-mentioned inorganic compound powder having an average particle diameter, and as shown in FIG. A moderate and uniform delay occurs in the contraction of No. 6, and the final contraction amount is also suppressed. As a result, the occurrence of warpage due to the difference in contraction with the ceramic green sheet 5 as shown in FIG. 13 is suppressed, and defects such as warpage and unevenness occur effectively in the laminated ceramic capacitor chip after firing. To be prevented. In the case of a monolithic ceramic capacitor, since the area of the internal electrode 6 is large, it is easily affected by the difference in contraction behavior between the internal electrode 6 and the ceramic green sheet 5, and the ripple effect by the application of the present invention is particularly large. On the other hand, for the via electrodes 3 and 8, a via electrode paste containing no inorganic compound powder is used, and the particle size of the metal powder is set to be larger than that of the wiring pattern layer paste, so that the filling rate in the via hole is increased. , Good conductivity. Further, as shown in FIG. 3, since the green sheets 5 for lamination are laminated after the via holes 4 are filled with the paste, the individual vias between the wiring pattern layers (internal electrodes) 6 are formed. There is an advantage that the density of the electrode portion can be increased.

As shown in FIG. 17, the via hole 4
Even if the stacking of the green sheets 5 for stacking without filling the paste into the via holes 4 and the paste filling of the stacked green sheets 5 into the via holes 4 are alternately performed, the paste filling into the via holes 4 is not performed. Since it is divided into units, the filling depth per time can be reduced and the density of individual via electrode portions between the wiring pattern layers (internal electrodes) 6 can be increased. In this embodiment, the second ceramic green sheet 13 having the third via electrode 15 is overlaid on the second ceramic green sheet 21 for the base portion and pressure-bonded, and the back tape 11 is peeled off at a predetermined position. A ceramic green sheet for lamination (internal electrode 6 is already formed) 5 having a via hole 4 formed therein is pressure-bonded and laminated (,), and the via hole 4 is filled with a paste to form a via electrode 8 (). . Further, another ceramic green sheet 5 is laminated and pressure-bonded (,) on the ceramic green sheet 5 on which the via electrode 8 is formed, and the via hole 4 of the sheet 5 is filled with paste to form the via electrode 8. ().

In the above embodiments, the laminated ceramic capacitor is taken as an example, but other than the capacitor,
The present invention can be applied to other monolithic ceramic electronic components such as monolithic ceramic inductors.

[Brief description of drawings]

FIG. 1 is a process explanatory view showing an example according to a first aspect of the present invention of a method for manufacturing a monolithic ceramic capacitor.

FIG. 2 is a diagram illustrating in detail the manufacturing process of the first ceramic green sheet for the base portion in FIG.

FIG. 3 is a diagram for explaining the manufacturing process of the laminated ceramic green sheet in detail.

FIG. 4 is an explanatory view of a stacking process of a ceramic green sheet for stacking.

FIG. 5 is an explanatory diagram following FIG. 4;

FIG. 6 is an explanatory diagram showing a completed state of a laminated green body when the process of FIG. 1 is used.

FIG. 7 is a view showing a cross-sectional structure of a surface mount type multilayer ceramic capacitor manufactured by using the multilayer green body of FIG.

FIG. 8 is an explanatory view of a manufacturing process of a ceramic green sheet by a doctor blade method.

FIG. 9 is a first inorganic compound powder in the second conductor powder.
FIG.

FIG. 10 is a schematic diagram showing a second formulation.

FIG. 11 is a schematic diagram showing a third compounding form.

FIG. 12 is a schematic view of a first conductor powder.

FIG. 13 is a diagram for explaining how warpage occurs due to firing shrinkage of a wiring pattern layer and a ceramic green sheet.

FIG. 14 is a diagram illustrating a state in which a wiring pattern layer made of only metal powder is greatly contracted.

FIG. 15 is a diagram illustrating a state of suppressing shrinkage by mixing an inorganic compound powder with a metal powder.

FIG. 16 is a diagram illustrating how warpage is prevented by suppressing the contraction.

FIG. 17 is a process explanatory view showing an example of a method for manufacturing a monolithic ceramic capacitor according to a second aspect of the present invention by extracting only the differences from the first aspect of the present invention.

[Explanation of symbols]

1, 5, 21 Ceramic green sheet (sheet body) 6 Internal electrode (wiring pattern layer, capacitor electrode) 6a First capacitor electrode 6b Second capacitor electrode 3,15 Via electrode 8 Via electrode (first conduction type via electrode) ) 8'via electrode (second conduction type via electrode) 11 back tape (resin film) 30 laminated green body 40 laminated ceramic capacitors 311 and 312 metal powder 317 type 1 inorganic compound powder 316 type 2 inorganic compound powder

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Manabu Sato             14-18 Takatsuji-cho, Mizuho-ku, Nagoya City, Aichi Prefecture             Inside this special ceramics company F-term (reference) 5E001 AB03 AE02 AH01 AH09 AJ01                       AJ02                 5E082 AB03 CC02 CC03 EE04 EE35                       FF05 FG26 FG46

Claims (8)

[Claims] 1. A plurality of laminating ceramic green sheets and wiring pattern layers are alternately laminated between a first base ceramic green sheet and a second ceramic green sheet, and 2 In the via hole formed so as to penetrate the laminated portion of the above-mentioned laminated ceramic green sheet, at least one of the plurality of laminated wiring pattern layers was formed with a via electrode which is electrically connected after firing. The second conductor powder forming the wiring pattern layer includes a metal powder and an inorganic compound powder having an average particle diameter of 500 nm or less, which includes a step of producing a laminated green body and a step of firing the laminated green body. Furthermore, the first conductor powder forming the via electrode does not contain an inorganic compound powder, or is less than the second conductor powder. And a filled ceramic green sheet for laminating, wherein in the step of producing the laminated green body, the via holes formed in the laminated ceramic green sheet are filled with the first conductor powder. After that, the filled ceramic green sheet for lamination is laminated on the main surface of either the first ceramic green sheet for the base portion or the ceramic green sheet for the second base portion. Manufacturing method of ceramic electronic components. 2. A plurality of laminating ceramic green sheets and wiring pattern layers are alternately laminated between the first base ceramic green sheet and the second ceramic green sheet, and 2 In the via hole formed so as to penetrate the laminated portion of the above-mentioned laminated ceramic green sheet, at least one of the plurality of laminated wiring pattern layers was formed with a via electrode which is electrically connected after firing. The second conductor powder forming the wiring pattern layer includes a metal powder and an inorganic compound powder having an average particle diameter of 500 nm or less, which includes a step of producing a laminated green body and a step of firing the laminated green body. Furthermore, the first conductor powder forming the via electrode does not contain an inorganic compound powder, or is less than the second conductor powder. In the step of producing the laminated green body, and
A step of laminating a laminating ceramic green sheet in a state in which the first conductor powder is not filled in the via hole on either main surface of the base ceramic green sheet or the second ceramic green sheet And a method of manufacturing the laminated ceramic electronic component, wherein the filling of the first conductor powder into the via holes of the laminated ceramic green sheets is alternately repeated. 3. The method for producing a laminated ceramic electronic component according to claim 1, wherein each time one of the laminated ceramic green sheets is laminated, the laminated laminated ceramic green sheet is pressed in the laminating direction. 4. A flip-chip type surface mounting device, wherein a part of the via electrode is formed on at least one surface of the first base ceramic green sheet and the second base ceramic green sheet. The method for producing a monolithic ceramic electronic component according to claim 1, wherein the monolithic ceramic electronic component is electrically connected to a terminal and the monolithic ceramic electronic component is produced as a surface mount type component. 5. The wiring pattern layer includes first and second capacitor electrodes facing each other with the laminated ceramic green sheet interposed therebetween, and the via electrode is electrically connected to the first capacitor electrode to form a second capacitor electrode. A first conductive type via electrode that is not conductive with the capacitor electrode of No. 2 and a second conductive type via electrode that is electrically conductive with the second capacitor electrode and is not conductive with the first capacitor electrode. The mounting terminal is formed as one that selectively conducts to either the first conductive type via electrode or the second conductive type via electrode, thereby manufacturing the surface mount type component as a surface mount type multilayer ceramic capacitor. The method for manufacturing a monolithic ceramic electronic component according to claim 4. 6. The method for manufacturing a laminated ceramic electronic component according to claim 1, wherein the inorganic compound powder has an average particle size smaller than that of the dielectric ceramic powder forming the ceramic green sheet. . 7. The inorganic compound powder comprises first type inorganic compound particles made of at least one of aluminum oxide, silicon dioxide and titanium oxide, and second type inorganic compound particles made of the same material as the dielectric ceramic layer. 7. The method for manufacturing a monolithic ceramic electronic component according to claim 1, further comprising at least one of the above. 8. The method for producing a laminated ceramic electronic component according to claim 7, wherein the second type inorganic compound powder contains a ferroelectric perovskite type oxide powder.