JP2003282332A - Ceramic electronic component and method of manufacturing the ceramic electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the fixing force of external conductors to an elemental ceramic body, without compromising the electrical characteristics of the conductors and, in addition, to accurately and quickly discriminate the quality of products. <P>SOLUTION: Borosilicate glass and a ceramic composition containing SiO<SB>2</SB>, BaCO<SB>3</SB>, Al<SB>2</SB>O<SB>3</SB>, etc., are mixed with each other so that the content of the borosilicate glass in the mixture becomes 60-72 wt.% and the elemental ceramic body 1, containing embedded internal electrodes 5, is formed from the mixture. In addition, paste for external electrode, containing the borosilicate glass in the amount of 3-5 wt.% with respect to Ag used as a conductive material, is prepared and external electrodes 2a and 2b are formed on the external surface of the ceramic body 1 by using the paste. The borosilicate glass contained in the paste can contain Cr<SB>2</SB>O<SB>3</SB>in the amount of 0.50-3.00 wt.%. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic electronic component and a method for manufacturing a ceramic electronic component, and more particularly, to a ceramic electronic component in which internal electrodes such as an internal conductor for a coil and an internal conductor for a capacitor are embedded, and its production. Regarding the method.

[0002]

2. Description of the Related Art In recent years, with the miniaturization of electronic equipment, ceramic substrates have been used for mounting electronic components constituting electronic circuits. Recently, multilayer ceramic substrates have been used from the viewpoint of increasing the mounting density. It is becoming widely used.

In this type of multilayer ceramic substrate, usually, after a conductor pattern is printed on the surface of the ceramic sheet by screen printing or the like, a suitable number of ceramic sheets having the conductor pattern are not formed with the conductor pattern. The ceramic sheet (exterior sheet) is sandwiched and pressure-bonded, and then the ceramic sheet and the conductor pattern are simultaneously fired to manufacture a ceramic element body in which the conductor pattern (internal electrode) is embedded. An external electrode is formed on the outer surface of the.

When manufacturing the ceramic body, it is desirable to suppress the energy required for firing as much as possible to obtain desired electrical characteristics. For that purpose, it is necessary to keep the firing temperature as low as possible.

Therefore, conventionally, as a ceramic composition which can be fired at a low temperature, SiO ₂ : 62 wt% to 75 wt
%, BaCO ₃ : 4 wt% to 22 wt%, Al ₂ O ₃ :
_{0.5wt% ~2.5wt%, Cr 2 O} 3: 0wt% ~
0.8 wt%, CaCO ₃ : 0.2 wt% to 0.8 wt
%, B ₂ O ₃ : 8 wt% to 18 wt%, K ₂ O: 0 wt%
% -2.5 wt% is proposed (Japanese Patent No. 3161355; hereinafter referred to as "prior art").

In the prior art, the firing treatment can be performed at a low temperature of 900 ° C. or lower, and since Ag having a low melting point can be used as the internal conductor, it is difficult to oxidize even in a high temperature atmosphere and Cu is used as the internal conductor. It is possible to perform a desired baking treatment without the need to make the baking atmosphere a reducing atmosphere as in the case of using.

[0007]

However, although the above-mentioned conventional technique is obtained by sintering the ceramic body at low temperature, as for the external electrodes, a normal Ag paste is printed on the outer surface of the ceramic body. Since it is formed by firing, there is a problem in that it is not possible to obtain a sufficient fixing force of the external electrode to the ceramic body.

Further, in the ceramic element body, as described above, the ceramic sheets are laminated and pressure-bonded, and then fired, so that the ceramic sheets are damaged or cracked or cracked during a series of manufacturing steps. Therefore, in the product inspection, a fluoroscopic inspection is performed with an optical microscope or the like to determine whether the internal electrodes are exposed on the surface of the ceramic body.

However, in the above-mentioned prior art, since the ceramic sheet can be seen through, the internal electrodes are exposed on the surface due to damage or the like in the ceramic sheet when the fluoroscopic inspection is performed, or the exterior is constituted. Since the ceramic sheet is transparent, it may be difficult to determine whether the internal electrodes appear to be exposed on the surface.
Therefore, there is a problem that the quality of the product cannot be judged quickly and accurately.

The present invention has been made in view of the above problems, and the fixing force of the external electrode to the ceramic body can be obtained without impairing the low temperature sinterability, electrical characteristics, mechanical strength and the like. It is an object of the present invention to provide a ceramic electronic component and a method for manufacturing the ceramic electronic component, which can improve the product quality and can quickly and accurately determine the quality of the product.

[0011]

The inventors of the present invention have used a porcelain composition containing borosilicate glass as a glass component capable of low-temperature sintering, and when the porcelain composition is used, electrical characteristics and In order to make the adhesion force of the external electrode to the ceramic element body stronger without deteriorating the mechanical strength, a diligent study was conducted, and it was 3 wt% to 5 wt% with respect to the conductive material.
It has been found that the borosilicate glass (1) can be included in the external electrode to improve the fixing force without impairing the electrical characteristics and solderability.

The present invention has been made on the basis of such findings, and a ceramic electronic component according to the present invention is a ceramic electronic component in which external electrodes are formed on the outer surface of the ceramic body. Is formed of a mixture of borosilicate glass and a porcelain composition prepared to have a predetermined composition, and the external electrode contains the borosilicate glass in an amount of 3% to 5% by weight relative to the conductive material. It is characterized by being.

According to the above structure, the borosilicate glass contained in the ceramic body is also contained in the external electrodes, and thus the adhesion between the ceramic body and the external electrodes can be improved.

Further, the present invention is characterized in that the porcelain composition contains at least silicon oxide, barium oxide, and aluminum oxide, whereby the dielectric constant, the insulation resistance and the like are improved. It is possible to easily obtain a ceramic electronic component having excellent adhesion of the external electrode to the ceramic body without impairing mechanical strength such as electrical characteristics and bending strength.

Further, the inventors of the present invention have conducted earnest researches so that the quality of the product can be quickly and accurately determined at the product inspection stage. As a result, 0.5% by weight of borosilicate glass is obtained.
It has been found that by adding a coloring agent containing 0% to 3.00% to the ceramic body, the transparency of the ceramic sheet is lowered, and thereby the recognition rate of product quality can be improved.

That is, the present invention is characterized in that a coloring agent containing 0.50% to 3.00% by weight of the borosilicate glass is added to the ceramic body.

According to the above construction, the coloring material (for example, chromium oxide) contained in the borosilicate glass in an amount of 0.50% to 3.00% by weight with respect to the borosilicate glass is contained in the ceramic element body. The outer surface of the element body is colored to reduce the transparency, which makes it possible to easily determine whether or not the surface of the internal electrode is exposed when the product is observed from the outside.

According to the present invention, a marking forming portion is provided at a predetermined position on the surface of the ceramic body, and a marking paste containing the borosilicate glass and the porcelain composition is applied to the marking forming portion. The marking paste is characterized by containing 18% to 26% by weight of the porcelain composition with respect to the borosilicate glass, and the marking paste contains copper, chromium, and manganese. It is characterized by containing a compound.

According to the above structure, since the marking forming portion, on which the marking paste is applied and fired, is formed at a predetermined position on the surface of the ceramic body, the marking forming portion is mounted in a desired direction on a wiring board such as a printed circuit board and mounted. Further, when the coil circuit is embedded inside, the direction of the magnetic force lines generated can be easily recognized even when a direct current is passed.

Further, the ceramic element body is characterized in that the internal electrodes having a predetermined pattern are embedded, so that a multilayer ceramic substrate having a built-in capacitor circuit and coil circuit inside the ceramic element body can be easily obtained. Therefore, the low-temperature sinterability and various electrical characteristics are not impaired, the adhesion of the external electrodes to the ceramic body is good, and product inspection can be performed with high accuracy. It is possible to easily obtain an excellent electronic component such as a multilayer ceramic substrate.

Further, in the method for producing a ceramic electronic component according to the present invention, a borosilicate glass and a porcelain composition prepared to have a predetermined component composition are mixed and then subjected to a predetermined firing treatment to produce a ceramic body. Then, a conductive paste containing 3% to 5% by weight of the borosilicate glass with respect to a conductive material is applied to the outer surface of the ceramic body and baked to form an external electrode.

According to the above manufacturing method, the required amount of borosilicate glass contained in the ceramic body can be contained in the external electrode as well, whereby the adhesion between the ceramic body and the external electrode is improved. A ceramic electronic component can be easily obtained.

Further, the manufacturing method of the present invention is characterized in that a coloring agent containing 0.50% to 3.00% by weight with respect to the borosilicate glass is added to the ceramic body.

According to the above manufacturing method, it is possible to easily obtain a ceramic body having a colored appearance, and to easily determine whether or not the internal electrodes are exposed on the surface.

In the manufacturing method of the present invention, the porcelain composition is contained in an amount of 18% to 26% by weight based on the borosilicate glass.
%, The marking paste is applied and fired on a predetermined portion of the surface of the ceramic body to mark it.

According to the above manufacturing method, it is possible to easily recognize the direction in which the manufactured electronic component should be mounted.

Further, in the manufacturing method of the present invention, the ceramic body is 60% by weight of the borosilicate glass.
72% is contained, and a ceramic sheet containing the borosilicate glass and the porcelain composition is prepared, a predetermined conductor pattern is formed on the surface of the ceramic sheet, and the conductor pattern is formed. The plurality of ceramic sheets are sandwiched between the ceramic sheets on which the conductor pattern is not formed and fired to form a ceramic body, which is excellent in the adhesive force to the ceramic body of the external electrode, Moreover, it is possible to easily manufacture a ceramic electronic component which is easy to inspect the product and has excellent mountability by firing at a low temperature.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view of a laminated inductance element as an embodiment of a ceramic electronic component according to the present invention. In the laminated inductance element, a large number of ceramic sheets 1a to 1l are laminated to form a ceramic body. 1 is formed. External electrodes 2a and 2b are formed on both ends of the ceramic body 1.
The first plating films 3a and 3b are formed on the surfaces of a and 2b, and the second plating films 4a and 4b are formed on the surfaces of the first plating films 3a and 3b.

Specifically, the ceramic body 1 has internal ceramic sheets 1d to 1i having internal electrodes 5a to 5g having a predetermined conductor pattern formed on the surface thereof, and the internal electrodes sandwiching the internal ceramic sheets 1d to 1i. The outer sheets 1a to 1c, 1k, and 1l in which the inner electrode 5a is not formed are electrically connected to the outer electrode 2a, and the inner electrode 5g is electrically connected to the outer electrode 2b. The internal electrodes 5a to 5g are electrically connected in series via via holes (not shown in FIG. 1) to form a coil.

A marking forming portion 6 is provided at a predetermined position on the upper surface of the ceramic body 1. The marking forming portion 6 is formed by applying and baking a marking paste described below, and when a direct current is applied to the internal electrodes 5a to 5g,
It is possible to recognize the direction of the generated magnetic force lines. For example, when elements are connected in series and the relative direction of the magnetic force lines generated by each coil causes an evaluation of the combined inductance when interactions such as coupling and decoupling occur. And controllable.

In the present embodiment, each of the ceramic sheets 1a to 1l comprises borosilicate glass containing SiO ₂ and B ₂ O ₃ as main components, SiO ₂ , BaO and Al ₂ O.
And a Ba-Al-Si-O-based porcelain composition containing ₃ and ₃ (hereinafter, simply referred to as "porcelain composition").

Specifically, borosilicate glass is B ₂ O.
₃ : 17.0 wt% to 21.0 wt%, K ₂ O: 1.0
wt% to 3.0 wt%, balance: SiO ₂ , and the porcelain composition is BaCO ₃ : 35.0 wt% to 39.0 wt.
%, Al ₂ O ₃ : 4.0 wt% to 5.0 wt%, Cr _{2
O 3: 0.5wt% ~1.5wt%,} CaCO 3: 0.
_{5wt% ~1.1wt%, B 2 O} 3: 2.0wt% ~
It is composed of 2.6 wt% and the balance: SiO ₂ , and is prepared so that the content ratio of the borosilicate glass is 60 wt% to 72 wt% with respect to the total amount of the borosilicate glass and the porcelain composition.

The external electrodes 2a and 2b are 30 w.
It is formed by applying and firing a conductive paste containing Ag powder containing t% of an organic vehicle as a main component.

In the present embodiment, 3 wt% to 5 wt% of borosilicate glass is added to Ag powder in the conductive paste. Therefore, the external electrodes 2a and 2b have the predetermined amount. Borosilicate glass is included, which improves the adhesion of the external electrodes 2a and 2b to the ceramic body 1.

The marking paste applied to the marking forming portion 6 contains Cu, Cr, and Mn in the composition component materials (borosilicate glass and porcelain composition) contained in the ceramic sheets 1a to 1l and the organic vehicle. A complex compound has been added.

Specifically, the marking paste is
A porcelain composition of 18 wt% to 26 wt% is added to the borosilicate glass, and a paste-like marking paste containing the porcelain composition, the borosilicate glass, the pigment, and the organic vehicle in predetermined amounts is provided in the marking forming portion 6. It is applied and baked.

The organic vehicle contained in the conductive paste and the colorant is not particularly limited, and ethyl cellulose dissolved in α-terpineol, butyral resin, acrylic resin or the like in a predetermined organic solvent. What was melt | dissolved can be used.

Next, the component composition of (1) the ceramic sheet, (2) the content of borosilicate glass in the external electrodes 2a and 2b, and (3) the content of the porcelain composition in the marking paste are as described above. The reasons for limitation will be described.

(1) Component Composition of Ceramic Sheet In the present embodiment, borosilicate glass is contained in the ceramic body 1 to enable low temperature sintering.
When the content of borosilicate glass is less than 60 wt%, the desired low temperature sintering action cannot be exhibited, and the firing temperature exceeds 900 ° C. On the other hand, when the content of borosilicate glass exceeds 72 wt%, the bending strength is 7.84 × 10.
^The mechanical strength is reduced to ⁷ Pa (≈800 kg / cm ² ) or less.

Therefore, in the present embodiment, the content of borosilicate glass in the ceramic body 1 is 60 wt% to 72%.
The raw material was adjusted to be wt%, preferably 64 wt% to 70 wt%.

(2) Content of Borosilicate Glass in External Electrodes 2a and 2b When the borosilicate glass forming the ceramic body 1 is also contained in the external electrodes 2a and 2b, the ceramic body 1 and the external electrode 2a are included. Borosilicate glass is mixed at the interface with the ceramic base body 1 of the external electrodes 2a and 2b.
The adhesion force to However, the content of borosilicate glass is 3 with respect to Ag which is the main component of the external electrodes 2a and 2b.
If it is less than wt%, the fixing force becomes 20 N (Newton) (about 2 kgf) or less, and the desired fixing force cannot be obtained. On the other hand, when the content of borosilicate glass with respect to Ag exceeds 5 wt%, the glass component is raised on the surfaces of the external electrodes 2a and 2b, and therefore the first plating film 3 is formed.
a and 3b are not formed uniformly, and as a result, the solderability is deteriorated.

Therefore, in the present embodiment, the external electrode 2
The content of borosilicate glass in a and 2b is 3 with respect to Ag.
wt% to 5 wt%, preferably 3.5 wt% to 4.5 w
It was made to be t%.

(3) Content of Porcelain Composition in Marking Paste The marking paste contains a complex oxide containing Cu, Cr and Mn, a porcelain composition and borosilicate glass. When the content of the porcelain composition exceeds 26 wt%, the content of borosilicate glass becomes small, making it difficult to sinter at low temperatures, and the firing temperature is 900.
Exceeds ℃. On the other hand, when the content of the porcelain composition with respect to the borosilicate glass is less than 18 wt%, the content of the borosilicate glass becomes excessive, and the manufactured components (multilayer inductance elements) adhere to each other.

Therefore, in the present embodiment, the content of the porcelain composition in the marking paste is 18 wt% to 26 wt%, preferably 21 wt% with respect to the borosilicate glass.
It was set to ˜25 wt%.

Next, a method of manufacturing the laminated inductance element will be described with reference to FIG.

First, the composition of ingredients is BaCO ₃ : 35.0 w.
t% to 39.0 wt%, Al ₂ O ₃ : 4.0 wt%
5.0 wt%, Cr ₂ O ₃ : 0.5 wt% to 1.5 wt
%, CaCO ₃ : 0.5 wt% to 1.1 wt%, B ₂ O
₃ : 2.0 wt% to 2.6 wt% and the balance: SiO ₂ , after mixing the composition raw materials and wet pulverizing, drying and calcination were performed, and the average particle diameter was 0.5 μm to 3. A 5 μm calcined powder is prepared. Then, the calcined powder and B ₂ O ₃ : 1
7.0 wt% to 21.0 wt%, K ₂ O: 1.0 wt%
˜3.0 wt%, balance: borosilicate glass having an average particle size of 0.5 μm to 3.5 μm prepared in SiO ₂ and mixed with water, an organic solvent, and a predetermined binder to form a slurry. It is produced and transferred onto a carrier film by a doctor blade method to produce thin ceramic sheets 1a to 1l.

The particle diameters of the borosilicate glass and the calcined powder are set within the range of the average particle diameter of 0.5 μm to 3.5 μm as described above. Pinholes in the ceramic sheet are reduced,
This is because the internal electrodes 5a to 5g in the ceramic body 1 are not short-circuited, and the sintering density is improved to increase the bending strength after firing.

Then, a conductive paste having a predetermined viscosity is prepared by mixing an Ag vehicle such as Ag or Ag-Pd with an organic vehicle, and as shown in FIG. 2, hook-shaped or U-shaped internal electrodes 5a-5g. Is screen-printed on the surfaces of the internal ceramic sheets 1d to 1j, and via holes 7 are formed at predetermined locations on the internal electrodes 5a to 5f.

Then, a borosilicate glass, a porcelain composition containing 18 wt% to 26 wt% of the borosilicate glass, a predetermined amount of a composite compound of copper, chromium and manganese, and an organic vehicle are mixed, and a three-roll mill is mixed. Use it to crush and disperse to make a marking paste.

Then, the marking forming portion 6 is provided at a predetermined position on the surface of the ceramic sheet 1a, and the marking paste is screen-printed on the marking forming portion 6.

As a method of forming and marking the internal electrodes 5a to 5f, any method such as a coating method, a vapor deposition method and a sputtering method can be used other than the screen printing.

Next, the internal ceramic sheets 1d to 1j
Is sandwiched between the exterior sheets 1a to 1c, 1k and 1l and pressure-bonded to produce a laminate. In the laminated body, the internal electrodes 5a to 5g are electrically connected in series via the via hole 7 to form a coil.

Then, the laminate is cut into a predetermined size, subjected to binder removal treatment at 500 ° C. in a mixed gas atmosphere of air and N _2, and then subjected to firing treatment at 850 ° C. to 900 ° C. for a predetermined time in the atmosphere. Then, barrel polishing and deburring are performed to produce the ceramic body 1.

Next, spherical Ag powder having an average particle size of 0.3 μm to 3 μm or flat Ag powder having an average particle size of 1 μm to 9 μm and borosilicate glass powder having an average particle size of 0.5 μm to 3.5 μm. , A predetermined amount of organic vehicle and mixed,
It is pulverized and dispersed by a three-roll mill to prepare an external electrode conductive paste having a predetermined viscosity (hereinafter, referred to as "external electrode paste").

Then, such an external electrode paste is applied to both ends of the ceramic body 1, and the temperature is 820 ° C. to 890.
A baking process is performed at 20 ° C. for 20 to 100 minutes, and then barrel polishing is performed to smooth the surface and form the external electrodes 2a and 2b.

After that, the ceramic body 1 having the external electrodes 2a and 2b formed thereon is dipped in a first predetermined plating solution such as a nickel plating solution, and the ceramic body 1 is used as a cathode.
An insoluble metal such as a titanium plate coated with t is used as an anode for electrolytic plating treatment to form a first plating film 3
a, 3b are formed and then immersed in a second predetermined plating solution such as a tin plating solution or a solder plating solution and subjected to the same electrolytic plating treatment as described above to form the second plating films 4a and 4b. Thus, the laminated inductance element is manufactured.

As described above, in this embodiment, the borosilicate glass contained in the ceramic body 1 is used as the external electrode 2.
3 wt% to 5 wt% of the conductive material is also contained in a and 2b. Therefore, borosilicate glass is mixed at the interface between the ceramic body 1 and the external electrodes 2a and 2b. Ceramic body 1 of 2a and 2b
It is possible to improve the adhesion force to the.

18 wt% relative to borosilicate glass
By using the marking paste containing ˜26 wt% of the porcelain composition, it is possible to perform marking at a low temperature firing process without causing mutual contact between the parts, and thereby direct current to the internal electrodes 5a to 5g. When shed
The direction of the generated magnetic force line can be easily recognized.

Furthermore, the present invention is not limited to the above-mentioned embodiment, and it is also preferable that the ceramic body 1 contains a predetermined amount of a colorant.

That is, after the laminated inductance element is manufactured, it is observed from the direction of the arrow A in FIG. 1 with an optical microscope or the like, and the internal electrodes 5a to 5a are damaged due to damage of the ceramic body 1.
It is necessary to inspect whether g is not exposed on the surface of the ceramic body 1 and to judge that the product exposed on the surface is defective in appearance and regard it as a defective product.

However, when the ceramic body 1 is formed of only a mixture of borosilicate glass and a porcelain composition, and the number of laminated outer sheets is small and thin, the ceramic body 1 is damaged even when the appearance is inspected. It may be difficult to determine whether the internal electrodes are exposed on the surface or whether the internal electrodes appear to be exposed due to the transparent ceramic sheet.

Therefore, it is preferable that the ceramic body 1 contains a colorant to facilitate the determination of the quality of the product.

Specifically, the ceramic sheets 1a to 1l
In addition, 0.50 wt% to 3 wt% with respect to borosilicate glass
Internal electrodes 5a to 5 by containing Cr ₂ O ₃ of
Whether or not the surface of g of the ceramic body 1 is exposed can be easily determined.

Here, the Cr ₂ O ₃ is limited to the above range, because when the Cr ₂ O ₃ content is less than 0.50 wt%, the coloring of the ceramic body 1 is insufficient, so that the internal electrode 5a.
~ 5g can be seen through, and the desired effect cannot be exhibited. On the other hand, when Cr ₂ O ₃ exceeds 3.00 wt%, the content of the borosilicate glass in the ceramic body is not limited to the range (60 wt% to 72 wt%) in the above embodiment. The dielectric constant ε
Exceeds 4.70, which causes deterioration of electrical characteristics, while
When the content of the borosilicate glass is set to the upper side, the flexural strength becomes 7.84 × 10 ⁷ Pa or less, and the mechanical strength is lowered.

Therefore, Cr ₂ for borosilicate glass
It is desirable to set the addition range of O ₃ to 0.50 wt% to ₃ wt%, preferably 2.00 wt% to 3.00 wt%.

The present invention is not limited to the above embodiment, but is applied to a laminated inductance element having a coil winding axis perpendicular to the external electrodes 9a and 9b as shown in FIG. It goes without saying that you can do it.

That is, in the laminated inductance element of FIG. 3, the ceramic element body 8 is formed with the internal ceramic sheets 8d to 8j on the surfaces of which the internal electrodes 12a to 12g having a predetermined conductive pattern are formed, and the internal electrodes. 8a to 8c, 8k, and 8l disposed on both side surfaces of the internal ceramic sheets 8d to 8j, the internal electrode 12a is electrically connected to the external electrode 9a, and the internal electrode 12g is connected to the external electrode 9b. It is electrically connected. And each internal electrode 12a-12g is electrically connected in series via a via hole, and forms the coil. 1
0a and 10b are first plating films, and 11a and 11
b is the second plating film, and the ceramic body 1
A marking forming portion 13 is provided at an appropriate place on the upper surface of the.

In this embodiment also, in order to carry out product inspection quickly and smoothly, 0.50 w is added to borosilicate glass.
t% to 3 wt%, preferably 2.00 wt% to 3.00
It is desirable to add wt% Cr ₂ O ₃ . That is, in the present embodiment, a fluoroscopic inspection is performed from the direction of arrow B with an optical microscope. However, when the distance (side gap) δ between the ceramic body 8 and the internal electrodes 12a to 12g is small, the internal electrode 12a is small. ~12g is sometimes difficult to determine whether or not the exposed surface, thus adding Cr ₂ O ₃ in the range described above, the presence or absence of surface exposure of the internal electrode by color the ceramic body 8 It is desirable to make decisions easily.

[0070]

EXAMPLES Next, examples of the present invention will be specifically described.

[First Example] The present inventors prepared ceramic element bodies (test pieces) having different mixing ratios of borosilicate glass and porcelain composition, and prepared the dielectric constant ε, the insulation resistance (resistivity). IR and bending strength were measured.

That is, first, the composition of the porcelain composition is BaCO ₃ : 35.0 wt% to 39.0 wt%, Al _{2
O 3: 4.0wt% ~5.0wt%,} Cr 2 O 3: 0.
5 wt% to 1.5 wt%, CaCO ₃ : 0.5 wt%
_{1.1wt%, B 2 O 3:} 2.0wt% ~2.6wt
%, Balance: SiO ₂ is weighed and mixed so that the constituents become SiO _2, and wet pulverized to form a slurry.
Calcinated at ℃ ~ 950 ℃, average particle size 0.5μm ~ 3.5
A calcined powder (porcelain composition powder) of μm was produced.

The same applies to borosilicate glass.
Ingredient composition is B ₂ O ₃ : 17.0 wt% to 21.0 wt.
%, K ₂ O: 1.0 wt% to 3.0 wt%, balance: Si
These constituent substances are weighed and mixed so as to be O _2, and wet-milled to form a slurry, which is then calcined at 850 ° C. to 900 ° C. A powder (borosilicate glass powder) was produced.

Next, the content of borosilicate glass is 72
wt% to 60 wt% (porcelain composition content is 28 wt%
-40% by weight), the calcined porcelain composition powder and the borosilicate glass powder are weighed, and the weighed material is water, an organic solvent such as toluene or ethyl alcohol,
And kneading with polyvinyl alcohol as a binder,
A slurry is prepared, and then the slurry is transferred onto a carrier film by a doctor blade method to give a thickness of 65 μm.
m ceramic sheet was obtained.

Next, these ceramic sheets are laminated and
Pressure bonding, thereby producing a laminated body with a thickness of 1.5 mm,
After cutting the laminated body into a plate shape having a length of 30 mm and a width of 30 mm, a binder removal treatment is performed at a temperature of 500 ° C. in a mixed gas atmosphere of air and N ₂ , and then in the air at 850 to 900.
The test pieces (ceramic element bodies) of Examples 1 to 7 were manufactured by firing at 90 ° C. for 90 minutes.

Further, the inventors of the present invention, as comparative examples, have a borosilicate glass content of 76 wt% to 74 wt% (porcelain composition content of 24 wt% to 26 wt%), and 58 w.
t% to 56 wt% (the content of the porcelain composition is 42 wt% to
(44 wt%), the calcined porcelain composition powder and the borosilicate glass powder are weighed, a laminate is prepared in the same manner as described above, and the binder removal treatment and the firing treatment are performed. -4 test pieces (ceramic element bodies) were produced.

Next, the present inventors measured the dielectric constant ε, the insulation resistance IR, and the flexural strength.

The dielectric constant ε is the RF impedance / material analyzer (“H” produced by Hewlett-Packard Co.
P4291A ”) was used, and the frequency was 100 MHz and the temperature was 25 ° C. In addition, the insulation resistance IR is
Using a micro ammeter (“R8340A” manufactured by Advantest), a DC voltage of 50 V was applied for 2 minutes at a temperature of 25 ° C., and measurement was performed. The bending strength was calculated according to JIS R 1601 by performing a test using a 3-point bending type bending strength measuring machine (RTC1225A manufactured by Orientec Co., Ltd.).

Table 1 shows the component composition of each test piece and its measurement result.

[0080]

[Table 1] In Table 1, the firing temperature indicates the temperature at which the maximum shrinkage rate is reached when each test piece shrinks as the test piece before firing rises in temperature as the binder evaporates and sinters. .

As is clear from Table 1, Comparative Examples 1 and 2
Since the content of borosilicate glass is too large, the bending strength becomes 7.84 × 10 ⁷ Pa or less, the mechanical strength tends to decrease, and the insulation resistance IR also tends to decrease.

Further, in Comparative Examples 3 and 4, since the content of borosilicate glass was small, the firing temperature exceeded 900 ° C., the low temperature sinterability was lacking, and the dielectric constant ε also exceeded 4.70. It has been confirmed that the characteristics of the electronic circuit deteriorate when the value is high.

On the other hand, in Examples 1 to 7, the content of borosilicate glass was 72 wt% to 60 wt%, which was within the range of the present invention, the dielectric constant ε was less than 4.70, and the insulation resistance IR was 6.3. × 10 ⁷ Ω · m or more, and bending strength is 7.84.
It was confirmed that it was possible to obtain good electrical characteristics and mechanical strength of x10 ⁷ Pa or more and to perform sintering at a low temperature of 900 ° C or lower.

[Second Example] The present inventors produced a ceramic sheet in the same manner as in the first example so that the component composition of Example 5 was obtained, and then printed the internal electrodes.
Next, the ceramic sheets were laminated and pressure-bonded, and then cut and fired to produce a ceramic body having a length of 1 mm, a width of 0.5 mm, and a thickness of 0.5 mm.

Then, an external electrode containing a glass component and a plating film were formed on both ends of the ceramic body, and the adhesive strength to the ceramic body and solderability were confirmed.

That is, first, 10% by weight of ethyl cellulose was dissolved in diethylene glycol monobutyl ether to prepare an organic vehicle.

The conductive material has an average particle size of 1.
Using 0 μm spherical Ag powder, the Ag powder and the borosilicate glass were weighed and mixed so that the content of the borosilicate glass with respect to the Ag powder was 3 wt% to 5 wt%, and the content of the organic vehicle was 30 wt%. To be crushed and dispersed using a three-roll mill, and then with diethylene glycol monobutyl ether to a viscosity of 1
The conductive paste was prepared by diluting to 8 Pa · s.

Then, a conductive paste was applied to both ends of the ceramic body, baked at 870 ° C. for 40 minutes in the atmosphere, and barrel-polished to form external electrodes.

Then, after that, the ceramic body having the external electrodes formed thereon was immersed in a nickel plating solution for electrolytic plating to form a nickel film (first plating film).

Then, the ceramic body on which the nickel film was formed was immersed in a tin plating solution for electrolytic plating to form a tin film (second plating film).
Thirty test pieces 1 to 13 were produced.

Further, the present inventors have found that the content of borosilicate glass with respect to Ag powder is 2 wt% or less, or 6 wt%.
A conductive paste prepared by weighing Ag powder and borosilicate glass as described above was prepared, and external electrodes, a nickel film and a tin film were sequentially formed in the same manner as described above, and Comparative Example 1
Thirty test pieces 1 to 14 were produced.

Next, each test piece is 12 mm long and 12 m wide.
m, 1.6 mm thick, mounted on a glass epoxy board, stress is applied to the side surface, and the breaking strength at that time is a strength tester (MODEL-1323N manufactured by Aiko Engineering Co., Ltd.)
And the sticking force was measured.

Further, the solder solution (S
The test piece was dipped in (n: Pb = 6: 4) for 2 seconds, and the solder adhesion area to the electrode was measured to evaluate the solderability.

Table 2 shows the composition of the conductive paste (external electrode) in each test piece, as well as the adhesive strength and solderability.

[0095]

[Table 2] In Table 2, the solderability was an average value of 30 test pieces, and the solderability was 95% and was regarded as a good product.

As is clear from Table 2, Comparative Example 11,
No. 12 has a borosilicate glass content of 3w with respect to Ag.
It was found that the adhesion strength was inferior to t% and the adhesion strength was less than 20 N (Newton).

Further, in Comparative Examples 13 and 14, the content of borosilicate glass with respect to Ag exceeded 5 wt%, and therefore the content of borosilicate glass was too large, so that the glass component came out on the surface of the external electrode, and as a result, It was found that the plating property deteriorates, and thus the solderability decreases to less than 95%.

On the other hand, in Examples 11 to 13, the content of borosilicate glass with respect to Ag was 3 wt% to 5 wt%, and the external electrode appropriately contained the glass component of the same component as the ceramic body. It was confirmed that the fixing force can be improved without impairing the solderability.

[Third Example] The present inventors produced a ceramic body having a marking forming portion marked by using the ceramic sheet having the composition of the above-mentioned Example 5,
External electrodes and a plating film were formed on both ends of the ceramic body, and the firing temperature and the adhesion ratio between test pieces (adhesion ratio between parts) were confirmed.

That is, first, the fifth embodiment of the first embodiment is described.
Borosilicate glass and porcelain composition having the same composition as described above are used, and the borosilicate glass and porcelain composition are weighed and mixed so that the content of the porcelain composition with respect to the borosilicate glass is 18 wt% to 26 wt%. Further, 12 wt% of a composite compound containing Cu, Cr, and Mn was added as a marking pigment, and the same organic vehicle as in the second example was used, and the content of the organic vehicle was 45 wt%. The mixture was blended as described above, pulverized and dispersed using a three-roll mill, and then diluted with diethylene glycol monobutyl ether until the viscosity became 30 Pa · s to prepare a marking paste.

Next, a marking paste is screen-printed on a predetermined portion of the surface of the ceramic sheet forming the uppermost layer of the ceramic body, and the internal ceramic sheet on which the internal electrodes are formed is subjected to the exterior sheet in the same manner as in the second embodiment. It was then sandwiched and pressure-bonded and fired to produce a ceramic body with a black marking portion.

Then, similarly to the second embodiment, a conductive paste is applied to both ends of the ceramic body, and the paste is heated to 87 in the air.
Baking treatment was performed at 0 ° C. for 40 minutes, then barrel polishing was performed to form an external electrode, and electrolytic plating was further performed to form a nickel film and a tin film, and 30 test pieces of Examples 21 to 25 were produced. .

Further, the present inventors have found that the content of the porcelain composition with respect to the borosilicate glass is 16 wt% or less, or 28%.
After preparing a marking paste in which borosilicate glass and a porcelain composition are weighed so as to be at least wt% and producing a ceramic body having a marking forming portion in the same manner as described above, an external electrode, a nickel film and a tin film are formed. By sequentially forming, 30 test pieces of Comparative Examples 21 to 25 were produced.

Next, the present inventors confirmed the firing temperature and the adhesion rate between parts for each test piece.

Table 3 shows the component composition of the marking paste, the firing temperature and the adhesion rate between parts.

[0106]

[Table 3] As is clear from Table 3, in Comparative Examples 21 to 23, since the content of the porcelain composition with respect to the borosilicate glass was less than 18 wt%, it was found that the inter-component adhesion ratio exceeded 1.00%.

Further, in Comparative Examples 24 and 25, the content of the porcelain composition with respect to the borosilicate glass exceeds 28 wt%, and the content of the borosilicate glass is relatively small, so the marking forming portion is burned at a low temperature. It has been found that it is difficult to bond and the firing temperature exceeds 900 ° C.

On the other hand, in Examples 21 to 25, the content of the porcelain composition with respect to the borosilicate glass was 18 wt% to 2%.
It was confirmed that the content was within the range of 6 wt%, the component adhesion ratio was less than 1.00%, and that sintering was possible at a low temperature of 900 ° C. or lower.

[Fourth Example] The present inventors produced a porcelain composition powder and a borosilicate glass powder as in the first example.

Next, the average particle size is 0.2 μm to 1.0 μm.
m of Cr ₂ O ₃ is 0.50 w with respect to borosilicate glass
Example 31 to Example 3 were added to the above porcelain composition powder and borosilicate glass powder so as to be t% to 3.00 wt% and one exterior sheet was used as in the case of the second example.
8 test pieces were prepared.

The inventors of the present invention also used the above C as a comparative example.
r_TwoO_ThreeTest pieces containing no (Comparative Examples 31, 3
2), and 4.00 wt% or less with respect to borosilicate glass
Cr on _TwoO_ThreeTest piece to which is added (Comparative Example 31 to Comparative Example
38) was produced.

Then, the present inventors measured the dielectric constant ε, the insulation resistance IR, and the flexural strength as in the first embodiment, and further measured the opacity of the conductor pattern as the internal electrode with an optical microscope (Nikon Corporation). It was observed with SMZ-2B manufactured by SMC.

Table 4 shows the composition of the ceramic body of each test piece and the measurement results.

[0114]

[Table 4] As is clear from Table 4, Comparative Example 31 and Comparative Example 32
Since Cr ₂ O ₃ is not separately added to the borosilicate glass, the internal electrodes can be seen through the ceramic sheet, and the internal electrodes may be exposed due to damage to the ceramic sheet. , It was difficult to determine whether the internal electrodes could be seen through the ceramic sheet.

Further, in Examples 33 to 38, since Cr ₂ O ₃ was separately added to the borosilicate glass, the ceramic sheet exhibited a black color. Therefore, it is possible to easily determine whether or not the surface of the internal electrode is exposed. However, the content of borosilicate glass in the porcelain composition is 60 wt.
˜70 wt% in the range of the first embodiment (the range of the present invention), when the borosilicate glass content is adjusted to 60 wt% and the lower side, the dielectric constant ε is 4 Electrical properties deteriorate beyond 70. On the other hand, when the content of borosilicate glass is adjusted to 70 wt% on the upper side, the bending strength becomes 7.84 × 10 ⁶ Pa or less and the mechanical strength Invite decline.

On the other hand, in Examples 31 to 34, Cr ₂ O was used.
₃ is 0.50 wt% to 1.0 with respect to borosilicate glass
Since the content of 0 wt% is included, the internal electrodes can be seen through a little, but it is possible to easily determine whether the internal electrodes are exposed on the surface.

In Examples 35 to 38, Cr ₂ O ₃ is 2.00 wt% to 3.00 wt% with respect to the borosilicate glass.
%, The internal electrode was not seen through the ceramic sheet and it was confirmed that the presence or absence of surface exposure of the internal electrode could be accurately and reliably determined.

[0118]

As described above in detail, the ceramic electronic component according to the present invention is a ceramic electronic component in which external electrodes are formed on the outer surface of the ceramic body, wherein the ceramic body is borosilicate glass and a predetermined composition. It is formed of a mixture with a porcelain composition containing at least silicon oxide, barium oxide, and aluminum oxide prepared as components, and the borosilicate glass is contained in the external electrode by weight relative to the conductive material. % Of 3% to 5%, it is possible to improve the fixing force of the external electrode to the ceramic body without impairing the electrical characteristics.

Further, according to the present invention, a coloring agent (for example, chromium oxide) containing 0.50% to 3.00% by weight with respect to the borosilicate glass is added to the ceramic body. The outer surface of the ceramic body is colored without impairing the electrical characteristics or the mechanical strength, and therefore, when the product is observed from the outside, the presence or absence of the surface exposure of the internal electrode can be easily determined.

Further, according to the present invention, a marking forming portion is provided at a predetermined position on the surface of the ceramic body, and the marking contains the borosilicate glass, the porcelain composition, and a complex compound containing copper, chromium, and magnesium. Since the paste is applied to the marking forming portion and the marking paste contains 18% to 26% by weight of the porcelain composition with respect to the borosilicate glass, low temperature sinterability is ensured. In addition, it is possible to prevent the parts from sticking to each other during the manufacturing process as much as possible, which makes it possible to easily attach and mount the wiring circuit board such as a printed circuit board in a desired direction and mount the coil circuit. Even if a direct current is applied when it is embedded inside, the direction of the magnetic field lines generated can be easily recognized, and the coupling and Interaction of such coupling also becomes possible to evaluate and control the total inductance generated.

Further, according to the present invention, the ceramic body is
Since the internal electrode consisting of a predetermined pattern is embedded,
Good adhesion to the ceramic body of the outer conductor without sacrificing low-temperature sinterability, various electrical characteristics and mechanical strength, high-precision product inspection, and excellent mountability. Electronic components such as a multilayer ceramic substrate can be easily obtained.

Further, in the method for manufacturing a ceramic electronic component according to the present invention, the borosilicate glass is mixed with the porcelain composition prepared to have a predetermined composition, and then a predetermined firing process is performed to produce a ceramic body. Then, the conductive paste containing the borosilicate glass in an amount of 3% to 5% by weight with respect to the conductive material is applied to the outer surface of the ceramic body and baked to form an external electrode. It is possible to easily manufacture a ceramic electronic component having excellent adhesion to the element body.

Further, in the manufacturing method of the present invention, the coloring agent is added to the borosilicate glass and the porcelain composition in an amount of 0.50% to 3.00% by weight based on the borosilicate glass, and then the predetermined amount is added. Since the above-mentioned firing is performed to produce the ceramic body, it is possible to easily obtain a ceramic electronic component whose appearance is colored without impairing electrical characteristics and mechanical strength.

Further, in the manufacturing method of the present invention, the porcelain composition is contained in an amount of 18% to 26% by weight based on the borosilicate glass.
% Of the marking paste is applied and fired on a predetermined surface of the ceramic body to mark,
It is possible to manufacture a ceramic electronic component that can be fired at a low temperature of 900 ° C. or less and that avoids contact between components as much as possible.

Further, in the manufacturing method of the present invention, the ceramic body is 60% to 7% by weight of the borosilicate glass.
A ceramic sheet containing 2% of the borosilicate glass and the porcelain composition was prepared, a predetermined conductor pattern was formed on the surface of the ceramic sheet, and a plurality of ceramic sheets having the conductor pattern were formed. Since the ceramic element body is formed by sandwiching and firing the ceramic sheet on which the conductor pattern is not formed, a high-quality and highly reliable ceramic electronic component having a capacitor circuit and a coil circuit inside the ceramic element body is formed. It can be easily manufactured.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a laminated inductance element as an electronic component according to the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing the laminated inductance element.

FIG. 3 is a cross-sectional view showing another embodiment of the laminated inductance element.

[Explanation of symbols]

1 Ceramic body 2a, 2b External electrode (electrode) 5 internal electrodes 6 Marking formation part

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01G 4/12 361 H01F 15/00 B 13/00 391 H01G 1/04 (72) Inventor Tomoyuki Maeda Kyoto Prefecture 2-26-10 Tenjin, Nagaokakyo, Murata Manufacturing Co., Ltd. (72) Inventor, Ryohei Kawabata 2-26-10 Tenjin, Tenjin, Nagaokakyo, Kyoto F-term (Reference), Murata Manufacturing 5E001 AB03 AE00 AE02 AF06 5E062 FG01 FG11 5E070 AA01 CB13 EA01 5E082 AB03 BC32 EE04 EE35 FG06 FG26 GG10 GG28 JJ03 JJ23 MM26 PP03

Claims (12)

[Claims] 1. A ceramic electronic component having external electrodes formed on the outer surface of a ceramic body, wherein the ceramic body is formed of a mixture of borosilicate glass and a porcelain composition prepared to have a predetermined composition. At the same time, the external electrode contains the borosilicate glass in an amount of 3% to 5% by weight with respect to the conductive material. 2. The ceramic electronic component according to claim 1, wherein the porcelain composition contains at least silicon oxide, barium oxide, and aluminum oxide. 3. The coloring material containing 0.50% to 3.00% by weight of the borosilicate glass is added to the ceramic body. The described ceramic electronic component. 4. The ceramic electronic component according to claim 3, wherein the colorant is chromium oxide. 5. A marking forming portion is provided at a predetermined position on the surface of the ceramic body, and a marking paste containing the borosilicate glass and the porcelain composition is applied to the marking forming portion, and the marking paste. The ceramic electronic component according to any one of claims 1 to 4, wherein 18% to 26% by weight of the porcelain composition is contained in the porcelain silicate glass. 6. The ceramic electronic component according to claim 5, wherein the marking paste contains a composite compound containing copper, chromium, and manganese. 7. The ceramic electronic component according to claim 1, wherein an internal electrode having a predetermined pattern is embedded in the ceramic body. 8. A borosilicate glass and a porcelain composition prepared to have a predetermined component composition are mixed and then subjected to a predetermined firing treatment to produce a ceramic body, and then the borosilicate glass is applied to a conductive material. A method for manufacturing a ceramic electronic component, comprising applying an electrically conductive paste, which is contained in an amount of 3% to 5% by weight, to the outer surface of the ceramic body to form an external electrode. 9. The production of a ceramic electronic component according to claim 8, wherein a coloring agent containing 0.50% to 3.00% by weight with respect to the borosilicate glass is added to the ceramic body. Method. 10. A marking paste containing 18% to 26% by weight of the porcelain composition with respect to the borosilicate glass is applied to predetermined locations on the surface of the ceramic body.
The method for manufacturing a ceramic electronic component according to claim 8 or 9, wherein the marking is performed by firing. 11. The ceramic electronic component according to claim 8, wherein the ceramic body contains 60% to 72% by weight of the borosilicate glass. Production method. 12. A ceramic sheet containing the borosilicate glass and the porcelain composition is prepared, a predetermined conductor pattern is formed on the surface of the ceramic sheet, and a plurality of ceramic sheets having the conductor pattern are formed. The method for producing a ceramic electronic component according to claim 8, wherein the ceramic element body is formed by sandwiching and firing the ceramic sheet on which no conductor pattern is formed.