WO2007072617A1

WO2007072617A1 - Ceramic electronic component and method for manufacturing same

Info

Publication number: WO2007072617A1
Application number: PCT/JP2006/319960
Authority: WO
Inventors: Daiji Kono; Kaoru Tachibana; Takehiko Otsuki
Original assignee: Murata Manufacturing Co., Ltd.
Priority date: 2005-12-23
Filing date: 2006-10-05
Publication date: 2007-06-28
Also published as: JP2009099572A

Abstract

A ceramic electronic component in which the part wetted with a conductive paste by immersion method can be stopped at a predetermined position and an external electrode can be formed with high dimensional precision. A ceramic electronic component wherein external electrodes (31) formed of a conductive paste are provided at the opposite ends of a ceramic laminate (10) incorporating a coil (L). The ceramic laminate (10) consists of a main portion (11) and end portions (12, 12). The end portion (12) has a porosity of 10 vol% or less whereas the main portion (11) has a porosity of 30-80 vol% thereby exhibiting a low wettability of the conductive paste. When the end portions (12, 12) are immersed into the conductive paste, upward wetting with the conductive paste is blocked at the border with the main portion (11) and the external electrode is formed with high dimensional precision.

Description

Ceramic electronic component and method for manufacturing the same

Technical field

TECHNICAL FIELD [0001] The present invention relates to a ceramic electronic component, and more particularly to a ceramic electronic component such as a chip inductor in which an electronic element such as a coil is incorporated in a ceramic laminate and a method for manufacturing the same. Background art

[0002] In general, various ceramic electronic parts such as chip inductors are provided in which a sheet made of ferrite and a coil conductor are laminated and a conductive paste is applied to both ends of the laminated body to form external electrodes. Has been. The external electrode is formed by immersing the end of the laminate in a thin paste layer or printing. The printing method is laborious and complicated, and is not practical in terms of cost. On the other hand, the dipping method is suitable for mass production, but it is difficult to prevent excessive wetting of the conductive paste, and the dimensional accuracy of the folded portion of the formed external electrode on the side of the laminate is poor. Have a point.

[0003] The wettability of the conductive paste varies depending on the surface state (porosity, roughness) or surface shape (recesses, presence of protrusions) of the laminate. Patent Document 1 includes, as shown in FIG. 11, an inner layer portion 115 having a porosity of 30 to 80 vol% and incorporating a coil L, and outer layer portions 116a and 116b having a porosity of 10 vol% or less. A ceramic electronic component comprising a ceramic laminate 120 is disclosed. However, in Patent Document 1, the external electrodes 121 provided at both ends of the laminate 120 are formed deep into the inner layer 115, and the difference in wettability between the inner layer 115 and the outer layer 116 a, 116 b is represented by the external electrode 121. There is no suggestion on how to use it for the formation.

Patent Document 1: Japanese Patent Laid-Open No. 2005-38904

Disclosure of the invention

Problems to be solved by the invention

[0004] Accordingly, an object of the present invention is to provide a ceramic electronic component that can stop the wetting of a conductive paste by a dipping method at a predetermined position and can form an external electrode with high dimensional accuracy, and a method for manufacturing the same. There is to do. Means for solving the problem

In order to achieve the above object, a first invention is a ceramic electronic component in which external electrodes formed using a conductive paste are provided at both ends of a ceramic laminate incorporating an electronic element, The laminate includes a main portion and an end portion provided with the external electrode, and the surface state of the main portion has lower wettability of the conductive paste than the surface state of the end portion. The surface of the part is formed up to the boundary part with the main part.

[0006] In the ceramic electronic component according to the first invention, when the conductive paste is applied to the end of the laminate, the conductive paste is prevented from wetting up at the boundary with the main part having low wettability, The external electrode is formed with high dimensional accuracy.

[0007] In the ceramic electronic component according to the first invention, the main part also has a ceramic laminated body force having a porosity of 30 to 80 vol%, and the end part also has a ceramic laminated body force having a porosity of 10 vol% or less. It is preferable to become. The pores may be filled with rosin. Further, even if the surface roughness of the main part is made larger than the surface roughness of the end part, the wetting of the conductive paste can be stopped at the boundary part with the main part.

[0008] A second invention is a ceramic electronic component in which external electrodes formed using a conductive paste V are provided at both ends of a ceramic laminated body incorporating an electronic element, the ceramic laminated body comprising: And an intermediate portion located between the main portion and the end portion, and the surface state of the intermediate portion is more wettable than the surface state of the end portion. The lower external electrode is formed on the surface of the end portion up to a boundary portion with the intermediate portion.

[0009] In the ceramic electronic component according to the second invention, when the conductive paste is applied to the end portion of the laminate, the conductive paste is prevented from wetting at the boundary with the intermediate portion having low wettability, The external electrode is formed with high dimensional accuracy.

[0010] In the ceramic electronic component according to the second invention, the intermediate portion also has a ceramic laminated body force having a porosity of 30 to 80 vol%, and the end portion also has a ceramic laminated body force having a porosity of 10 vol% or less. It is preferable to become. The pores may be filled with rosin. Even if the surface roughness of the intermediate part is made larger than the surface roughness of the edge part, the wetting of the conductive paste can be reduced with the intermediate part. Can be stopped at the boundary.

[0011] A third invention is a ceramic electronic component in which external electrodes formed using a conductive paste V are provided at both ends of a ceramic laminate incorporating an electronic element, the ceramic laminate being a main component. Part and an end provided with the external electrode, in plan view from the arrangement direction of the main part and the end part, the end part is formed inside the outer periphery of the main part, the external electrode is The surface of the end portion is formed up to the boundary portion with the main portion.

[0012] In the ceramic electronic component according to the third invention, when the conductive paste is applied to the end portion of the multilayer body, the conductive paste is prevented from getting wet at the boundary portion with the main portion where the step exists. The external electrodes are formed with high accuracy in terms of dimensions.

[0013] A fourth invention is a ceramic electronic component in which external electrodes formed using a conductive paste V are provided at both ends of a ceramic laminate incorporating an electronic element, the ceramic laminate being a main component. And an intermediate portion positioned between the main portion and the end portion, and the intermediate portion is provided in a concave shape between the main portion and the end portion. The external electrode is formed on the surface of the end portion up to a boundary portion with the intermediate portion or the main portion.

[0014] In the ceramic electronic component according to the fourth aspect of the invention, when the conductive paste is applied to the end of the laminate, the conductive paste is prevented from wetting at the concave intermediate portion, and the external electrode is It is formed with high dimensional accuracy.

[0015] A fifth invention is a ceramic electronic component in which external electrodes formed using a conductive paste V are provided at both ends of a ceramic laminated body incorporating an electronic element, the ceramic laminated body comprising: And an intermediate part located between the main part and the end part, and the intermediate part is provided in a convex shape between the main part and the end part, The external electrode is formed on the surface of the end portion up to a boundary portion with the intermediate portion.

[0016] In the ceramic electronic component according to the fifth invention, when the conductive paste is applied to the end of the laminate, the conductive paste is prevented from getting wet at the boundary with the intermediate portion where there is a step. The external electrodes are formed with high accuracy in terms of dimensions. [0017] According to a sixth aspect of the present invention, a conductive paste is used at both ends of a ceramic laminate incorporating an electronic element.

V, a method of manufacturing a ceramic electronic component provided with external electrodes formed by laminating ceramic sheets, a main part having a surface state in which the wettability of the conductive paste is relatively low, and the wettability of the conductive paste Forming a laminate composed of an end portion having a relatively high surface state, and applying a conductive paste to the surface of the end portion to form an external electrode up to a boundary portion with the main portion. It is characterized by having.

[0018] In the method for manufacturing a ceramic electronic component according to the sixth aspect of the invention, when applying the conductive paste to the end of the laminate, the conductive paste has low wettability and wets at the boundary with the main part. The force S is prevented, and the external electrode is formed with high dimensional accuracy.

[0019] A seventh invention is a method for manufacturing a ceramic electronic component in which external electrodes formed using a conductive paste V are provided at both ends of a ceramic laminate incorporating an electronic element, wherein the ceramic sheets are laminated. A main portion, an end portion having a surface state with relatively high wettability of the conductive paste, and a relatively low wettability of the conductive paste and having a surface state between the main portion and the end portion. A step of forming a laminated body comprising: an intermediate portion positioned; and a step of applying a conductive paste to the surface of the end portion to form an external electrode up to a boundary portion with the intermediate portion. And

[0020] In the method for manufacturing a ceramic electronic component according to the seventh aspect of the invention, when applying the conductive paste to the end portion of the laminate, the conductive paste has a wetting force at the boundary with the intermediate portion having low wettability. S is prevented, and the external electrode is formed with high dimensional accuracy.

[0021] In the method of manufacturing a ceramic electronic component according to the sixth and seventh inventions, the main part or the intermediate part having a surface state in which the wettability of the conductive paste is relatively low, the ceramic raw material power containing a burned-out material is also ceramic. It is preferable to form a green sheet by laminating the sheets.

[0022] An eighth invention is a method for manufacturing a ceramic electronic component in which external electrodes formed using a conductive paste V are provided at both ends of a ceramic laminate incorporating electronic elements, the ceramic sheets being laminated The main portion and end portions located at both ends of the main portion, and the end portion is arranged on the inner side of the outer periphery of the main portion in plan view. V, forming the laminated body, and applying an electrically conductive paste to the surface of the end portion to form an external electrode And a step of forming up to a boundary portion with the main portion.

[0023] In the method for manufacturing a ceramic electronic component according to the eighth aspect of the invention, when the conductive paste is applied to the end of the laminate, the conductive paste wets up at the boundary with the main part where there is a step. The external electrode is formed with high accuracy in terms of dimension.

[0024] A ninth invention is a method of manufacturing a ceramic electronic component in which an external electrode formed by using a conductive paste V is provided at both ends of a ceramic laminate incorporating an electronic element, wherein the ceramic sheet is laminated. And the intermediate part located between the main part and the end part and the main part and the end part, and the laminated body so that the surface shape of the intermediate part is different from the surface shape of the main part and the end part. And a step of applying a conductive paste to the surface of the end portion to form an external electrode up to the intermediate portion or the boundary portion with the main portion. For example, the surface shape of the intermediate portion can be formed in a concave shape or a convex shape with respect to the main portion and the end portion to have different shapes.

[0025] In the method of manufacturing a ceramic electronic component according to the ninth aspect of the invention, when applying the conductive paste to the end portion of the laminate, the conductive paste has a wetting force at the boundary with the intermediate portion having a different shape. Thus, the external electrode is formed with high dimensional accuracy.

In the method for manufacturing a ceramic electronic component according to the sixth to ninth inventions, the external electrode is preferably formed by immersing the end of the multilayer body in a conductive paste. Ceramic electronic parts equipped with external electrodes with good dimensional accuracy can be mass-produced at low cost.

[0027] In the present invention, the external electrodes are formed by using a conductive paste at both ends of the ceramic laminate, and the conductive paste applied to both ends of the ceramic laminate is baked or conductive grease is used. If it is a material, it means that it is cured after application.

The invention's effect

[0028] According to the present invention, when forming the external electrode at the end of the laminate, the wetting force S of the conductive paste is prevented at the boundary between the end and the main part or the intermediate part. The dimension of the folded portion to the side surface of the laminate can be accurately formed.

Brief Description of Drawings

FIG. 1 is a cross-sectional view schematically showing a ceramic electronic component which is a first embodiment of the present invention.

FIG. 2 is an exploded perspective view of the ceramic electronic component. FIG. 3 is a cross-sectional view of a main part of the ceramic electronic component.

FIG. 4 is a sectional view schematically showing a ceramic electronic component according to a second embodiment of the present invention.

FIG. 5 is a sectional view schematically showing a ceramic electronic component according to a third embodiment of the present invention.

FIG. 6 is a cross-sectional view schematically showing a ceramic electronic component according to a fourth embodiment of the present invention.

FIG. 7 shows a ceramic electronic component according to a fifth embodiment of the present invention, in which (A) is a schematic cross-sectional view, and (B) is a view taken in the direction of arrow A with the external electrode omitted.

FIG. 8 is a sectional view schematically showing a ceramic electronic component according to a sixth embodiment of the present invention.

FIG. 9 is a sectional view schematically showing a ceramic electronic component according to a seventh embodiment of the present invention.

FIG. 10 is an explanatory diagram showing a state in which a conductive paste is applied to the end of a ceramic electronic component

FIG. 11 is a cross-sectional view showing a conventional ceramic electronic component.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of a ceramic electronic component and a manufacturing method thereof according to the present invention will be described with reference to the accompanying drawings.

[0031] (Refer to the first embodiment, FIGS. 1 to 3)

As shown in FIG. 1, the ceramic electronic component 1A according to the first embodiment of the present invention includes a coil L built in the laminate 10 and external electrodes 31 and 31 that are electrically connected to the coil L at both ends of the laminate 10. It is configured as a formed chip inductor.

As shown in FIG. 2, the laminate 10 is made by laminating a plurality of ceramic sheets 15 having a predetermined pattern of coil conductors 21 and a plurality of ceramic sheets 16 having via-hole conductors 25, and firing them. Is formed. Each coil conductor 21 forms a helical coil L via a via-hole conductor 22 formed at one end, and both ends of the coil L are electrically connected to the external electrodes 31 and 31 by via-hole conductors 25. Yes.

Here, the laminated portion of the ceramic sheet 15 is referred to as a main portion 11 of the laminated body 10, and the laminated portion of the ceramic sheet 16 is referred to as end portions 12 and 12. The main part 11 has a porosity of 30 to 80 vol%, and the end parts 12 and 12 have a porosity of 10 vol% or less. If the porosity is less than or equal to lOvol%, the voids are generated by bubbles or binders and dispersants volatile components encapsulated when the slurry-like ceramic material is produced. Higher porosity than ceramic materials An appropriate amount of burned-out material can be added and fired to obtain it. In addition, these pores may be filled with an epoxy resin. As burned-out materials, those that also have cross-linked polystyrene strength are known. FIG. 3 shows a state in which holes 35 are formed in the laminate 10 and filled with the resin 36. The holes 35 include open holes and closed holes.

[0034] By forming the holes 35 in the stacked body 10, the dielectric constant is lowered and the stray capacitance is reduced, so that desired impedance characteristics can be obtained. In this case, when the porosity exceeds 80 vol%, which is preferably 30 vol% or more, the mechanical strength of the laminate 10 decreases. On the other hand, by setting the porosity of the end portions 12 and 12 to 10 vol% or less, the conductive base applied as the external electrodes 31 and 31 is diffused into the laminated body 10. In addition, since the magnetic permeability increases, the leakage of magnetic flux in the coil L is reduced. Filling the pores 35 with the resin 36 has an effect of suppressing a decrease in impedance.

[0035] Here, the porosity (Vol%) is obtained by the following equation.

Porosity = (1-(W / V) / G) X 100 (%)

W: Weight of ceramic sintered body

V: Volume of ceramic sintered body

G: Theoretical density of ceramic sintered body

Meanwhile, the external electrodes 31, 31 are formed by applying a conductive paste to the surfaces of the end portions 12, 12 of the multilayer body 10 by an immersion method. That is, as shown in FIG. 10, a flat stainless steel tank 50 is filled with a conductive paste P to a predetermined thickness, and a plurality of laminates 10 held on the back surface of the jig 51 are attached to the jig 51. By lowering, the end surface force of the laminate 10 is immersed in the conductive paste P until it contacts the bottom surface of the stainless steel tank 50, pulled up, and then dried.

[0037] In general, the wettability of the conductive paste with respect to the laminate varies depending on the surface state of the laminate. When the porosity of the laminate is small, the wettability is relatively large. When the porosity is large, the wettability is relatively small. In the first embodiment, the main part 11 is formed with a porosity of 30 to 80 vol%, and the end part is formed with a porosity of 10 vol% or less, so that the end part 12 of the laminate 10 is electrically conductive. When immersed in the paste P, the conductive paste P has low wettability and prevents the wetting due to surface tension at the boundary with the main part 11. Therefore, the external electrode 31 is dimensionally It will be formed accurately. The dimensional accuracy of the external electrode 31 in the first embodiment will be described below together with a comparative example as an experimental result by the present inventors.

[0038] Here, a method of manufacturing a ceramic electronic component will be described. There are two types of manufacturing methods. In the first method, a desired pattern is formed on a ceramic green sheet having a through-hole by a printing method such as screen printing using a conductive paste, and the sheet is laminated and crimped so that a spiral coil is formed. Ceramic electronic parts are obtained by cutting and firing. In the second method, ceramic materials and conductor materials are alternately printed by a printing method such as screen printing to form a helical coil, and a ceramic electronic component is obtained by pressure bonding, cutting, and firing.

[0039] Specifically, the ceramic electronic component 1A was manufactured by the following steps. First, the oxide materials of -keckle, zinc, copper and iron were mixed and calcined at 800 ° C for 1 hour. Thereafter, the raw material was pulverized by a ball mill and dried to obtain a Ni—Zn—Cu ferrite raw material having an average particle diameter of about 2 m. Next, a solvent, a binder and a dispersant were added to the ferrite raw material and kneaded to obtain a slurry.

[0040] The sheet 16 constituting the end portions 12 and 12 was formed into a ceramic green sheet having a thickness of 40 m by the doctor-blade method using the slurry-like ferrite raw material. For the sheet 15 constituting the main part 11, in addition to the above-mentioned ferrite raw material, a commercially available spherical polymer, for example, a burned-out material having an average particle size of 8 / zm and having a crosslinked polystyrene power is added. Then, they were kneaded to form a slurry, and a ceramic green sheet having a thickness of 40 μm was obtained by a doctor blade method or the like.

[0041] A hole for a via-hole conductor was formed in the prepared ceramic green sheet, and a coil conductor or a via-hole conductor was screen-printed. For printing, we used conductive paste such as Ag, Pd, Cu, Au and their alloys.

Next, as shown in FIG. 2, the sheets 15 and 16 were laminated and pressure-bonded to produce a laminated body 10 in which the coil L was built. The above process is performed in a state where a plurality of coils are arranged in a matrix as a mother substrate, and the mother laminate is cut into one unit laminate (chip). Then, the obtained laminate was heat-treated at 400 ° C. for 3 hours (debinding agent treatment) and then baked at 925 ° C. for 2 hours. From the main part 11 and the end parts 12, 12 having the desired porosity A sintered ceramic laminate 10 is obtained.

Next, the ceramic sintered laminate 10 was immersed in an epoxy-based resin, the resin was filled in the pores, and the resin was cured at 150 to 180 ° C. for 2 hours. After removing the resin film adhering to the surface of the laminate 10, a conductive paste made of Ag is applied to the surfaces of the end portions 12 and 12 of the laminate 10 using the coating apparatus shown in FIG. 31, 31 were formed.

[0044] The present inventors produced a ceramic sintered laminate 10 having a long side of 1. Omm, a short side of 0.5mm, and a height of 0.5mm by the above-described process. The end portions 12 and 12 having a porosity of 10 vol% or less are set to 200 m (dimension W1) from the end face, and the main portion 11 contains about 5 μm pores with a porosity of about 50 vol%. A conductive paste mainly composed of Ag was applied to the end portion. The viscosity of the conductive paste was 31.4 Pa.s when the shear rate was about 1.9 sec-1.

That is, as shown in FIG. 10, 100 ceramic sintered laminates 10 are held on the back surface of the jig 51, and the conductive paste Ρ is put into the stainless steel tank 50 to a depth of 150 μm. The surface of the paste P was smoothed using a squeegee. The jig 51 was lowered until the end surface of the laminate 10 was in contact with the bottom surface of the stainless steel tank 50, and the conductive paste P was applied to the end 12 of the laminate 10. After coating, it was dried in an oven at 120 ° C for 1 hour. The dimension W2 of the folded portion of the external electrode 31 formed here was determined.

[0046] Specifically, the conductive paste is applied only to one end of the laminate 10 and dried, and the dimension W is subtracted from the dimension W measured in advance from the length L of the laminate 10. We asked for W2. The results are shown in Table 1 below.

[0047] As a comparative example, a laminated body formed of a ceramic material having the same size as the laminated body 10 and the main portion 11 being the same as the end portions 12 and 12 (mixed with a burned-out material) is shown in FIG. A conductive paste (150 m in depth) was applied to the end using the coating apparatus shown in Fig. 1, and dried under the same conditions, and the dimensions of the folded portion of the formed external electrode were determined. The results are also shown in Table 1.

[0048] [Table 1] 1)

[0049] In the comparative example, by immersing in a conductive paste with a thickness of 150 m, the folded part has a minimum dimension of 205 μm and a maximum of 232 μm. It will be a great help. On the other hand, in the first embodiment, the dimension W2 of the folded portion is 203 μm at the minimum, 215 μm at the maximum, and 208 μm on the average, which is a preferable dimensional accuracy. This is because wetting of the conductive paste was stopped at the boundary with the main part having a large porosity. In Table 1, σ represents the magnitude of variation with standard deviation.

[0050] It should be noted that since the pores are not necessarily formed in the boundary portion between the main portion 11 and the end portions 12 and 12, the external electrode 31 is formed to the inside of about 10 to 20 m from the boundary. .

[0051] (Refer to the second embodiment, FIG. 4)

As shown in FIG. 4, the ceramic electronic component 1B according to the second embodiment is formed of a laminated body 10 with a main part 11, end parts 12, 12 at both ends, and intermediate parts 13, 13. Only 13 had a porosity of 30 to 80 vol%. The porosity of the main part 11 and the end parts 12 and 12 is 10 vol% or less. The width of the intermediate parts 13 and 13 is 20 m. In FIG. 4, the internal coils are not shown.

[0052] In the second embodiment, when the conductive paste is applied to the end portions 12 and 12, the conductive paste has a boundary portion with the intermediate portions 13 and 13 having a high porosity (the surface has low wettability). The wetting is prevented and the external electrode 31 is formed with high dimensional accuracy.

[0053] (Refer to the third embodiment, FIG. 5)

As shown in FIG. 5, the ceramic electronic component 1C according to the third embodiment is formed of a laminated body 10 with a main part 11 and end parts 12 and 12 at both ends, and the end parts 12 and 12 have a normal surface roughness. The surface roughness Ra of the main part 11 is set to 1.45 / zm, for example, while it is (Ra: about 0.81 / zm). In addition In FIG. 5, the internal coils are not shown.

[0054] When the surface roughness is rough, the wettability of the conductive paste decreases. Therefore, also in the third embodiment, when the conductive paste is applied to the end portions 12 and 12, the conductive paste has a rough surface (the surface has low wettability) at the boundary portion with the main portion 11. The wetting is prevented, and the external electrode 31 is formed with high dimensional accuracy.

[0055] (Example 4 see FIG. 6)

As shown in FIG. 6, the ceramic electronic component 1D according to the fourth embodiment includes a laminated body 10 formed of a main part 11, end parts 12, 12 at both ends, and intermediate parts 13, 13. Only the surface roughness Ra is set to 1.45 / zm, for example, and the surface roughness of the main part 11 and the end parts 12 and 12 is assumed to be a normal surface roughness. In FIG. 6, the internal coils are not shown.

Also in the fourth embodiment, when the conductive paste is applied to the end portions 12 and 12, the conductive paste is prevented from wetting at the boundary portions with the intermediate portions 13 and 13 having a rough surface, and the external electrode 3 1 is formed with high dimensional accuracy.

[0057] (Fifth embodiment, see FIG. 7)

As shown in FIG. 7, the ceramic electronic component 1E according to the fifth embodiment is formed of a laminated body 10 with a main part 11 and end parts 12 and 12 at both ends. The end portions 12 and 12 are formed inside the outer periphery of the main portion 11 in a plan view from the arrangement direction (the direction of arrow A). In this case, the main part 11 and the end parts 12 and 12 are different from each other only in the outer shape which may be made of the same material. In FIG. 7, the internal coils are not shown. FIG. 7 (B) is a view seen from the direction of arrow A in FIG. 7 (A).

In the fifth embodiment, when applying the conductive paste to the end portions 12, 12, the conductive paste is prevented from wetting at the step portion between the end portions 12, 12 and the main portion 11, and the external electrode 31 Is formed with dimensional accuracy.

[0059] (Refer to Example 6, Fig. 8)

As shown in FIG. 8, the ceramic electronic component 1F according to the sixth embodiment is formed of a laminated body 10 with a main part 11, end parts 12 and 12 at both ends, and intermediate parts 13 and 13. A concave groove 13a is formed. By forming the groove 13a in the intermediate portion 13, when the conductive paste is applied to the end portions 12, 12, the wetting of the conductive paste is prevented by the groove 13a, and the external electrode 31 is It is formed with high accuracy in dimension.

[0060] The present inventors have described the ceramic sintered laminate 10 of the sixth embodiment having a long side of 1. Omm, a short side of 0.5mm, and a height of 0.5mm described in the first embodiment. It was produced in. Furthermore, grooves 13a and 13a having a width of 20 μm and a depth of 10 μm were formed on the inner surface J of the laminated body 10 having an end face force of 150 m (dimension W3). A conductive paste mainly composed of Ag was applied to the end portions 12 and 12. The viscosity of the conductive paste was 12.5 Pa.s when the shear rate was about 1.9 sec- ¹ .

That is, as shown in FIG. 10, 100 ceramic sintered laminates 10 are held on the back surface of the jig 51, and a conductive paste tub is introduced into the stainless steel bath 50 to a depth of 100 μm. The surface of the paste P was smoothed using a squeegee. The jig 51 was lowered until the end surface of the laminate 10 was in contact with the bottom surface of the stainless steel tank 50, and the conductive paste P was applied to the end 12 of the laminate 10. After coating, it was dried in an oven at 120 ° C for 1 hour. The dimension W4 of the folded portion of the external electrode 31 formed here was determined by the same procedure as the dimension W2 in the first example. The results are shown in Table 2 below.

[0062] As a comparative example, a conductive paste (with the same depth of 100 μm) was applied to the end of a laminated body of the same size that does not form a groove using the coating apparatus shown in FIG. The dimensions of the folded portion of the formed external electrode were determined. The results are also shown in Table 2.

[0063] [Table 2]

2)

In the comparative example, the dimension of the folded part was 166 m at the minimum and 198 m at the maximum by dipping in a conductive paste with a thickness of 100 / zm, and the surface tension increased to 182 m on average. become. On the other hand, in the sixth embodiment, the dimension W4 of the folded portion is a minimum of 164 μm, a maximum of 176 μm, and an average of 173 μm, which is a preferable dimensional accuracy. This This is because the wetting of the conductive paste is stopped by the groove 13a of the intermediate portion 13.

[0065] In the sixth embodiment, the wetting of the conductive paste is not completely stopped by the groove 13a. When the depth of the groove 13a is 10 m, wetting up stops on the inner side about 13 m from the intermediate portion 13.

[0066] (Refer to the seventh embodiment, FIG. 9)

As shown in FIG. 9, the ceramic electronic component 1G according to the seventh embodiment includes a laminate 10 as a main part.

11, end portions 12 and 12 at both ends, and intermediate portions 13 and 13, and a convex protrusion 13 b is formed on the intermediate portion 13. By forming the protrusion 13b on the intermediate portion 13, when the conductive paste is applied to the end portions 12, 12, the wetting of the conductive paste is prevented by the protrusion 13b, and the external electrode 31 is formed with high dimensional accuracy. Will be.

[0067] (Other Examples)

It should be noted that the ceramic electronic component and the manufacturing method thereof according to the present invention can be variously modified within the scope of the gist thereof, which is not limited to the above embodiment.

For example, the present invention can be widely applied to various ceramic electronic parts such as LC composite parts in addition to the chip inductors shown in the above embodiments. In the third to seventh embodiments, the porosity of the main part 11, the end part 12 and the intermediate part 13 is arbitrary, and the pores may not be filled with grease.

[0069] Further, the above-described embodiments can be combined. For example, the fifth embodiment in which the laminated body is composed of a main part and an end part, and the end part is formed inside the outer periphery of the main part (see FIG.

7)), the main part may have a porosity of 30 to 80 vol%, and the end part may have a porosity of 10 vol% or less.

Industrial applicability

[0070] As described above, the present invention is useful for ceramic electronic components such as chip inductors, and in particular, the wetting of the conductive paste by the dipping method can be stopped at a predetermined position, and external electrodes can be formed with high dimensional accuracy. Excellent in that it can be done.

Claims

The scope of the claims

[1] A ceramic electronic component having external electrodes formed using a conductive paste at both ends of a ceramic laminate incorporating an electronic element,

The ceramic laminate includes a main part and an end provided with the external electrode, and the surface state of the main part is lower in wettability of the conductive paste than the surface state of the end part. The external electrode is the end part. Formed on the surface of the main part up to the boundary with the main part,

Ceramic electronic parts characterized by

[2] The main part also has a ceramic laminated body force having a porosity of 30 to 80 vol%, and the end part also has a ceramic laminated body force having a porosity of 10 vol% or less. The ceramic electronic component according to item 1.

[3] The ceramic electronic component as set forth in [2], wherein the pores formed in the ceramic laminate are filled with resin.

[4] The ceramic electronic component according to [1], wherein a surface roughness of the main portion is rougher than a surface roughness of the end portion.

[5] A ceramic electronic component provided with external electrodes formed using a conductive paste at both ends of a ceramic laminate incorporating an electronic element,

The ceramic laminate includes a main part, an end provided with the external electrode, and an intermediate part located between the main part and the end,

The surface state of the intermediate part is lower in wettability of the conductive paste than the surface state of the end part, and the external electrode is formed up to the boundary part with the intermediate part on the surface of the end part.

Ceramic electronic parts characterized by

6. The intermediate portion also has a ceramic laminate force having a porosity of 30 to 80 vol%, and the end portion also has a ceramic laminate force having a porosity of 10 vol% or less. The ceramic electronic component according to Item 5.

[7] The ceramic electronic component as set forth in [6], wherein the pores formed in the ceramic laminate are filled with resin.

8. The ceramic electronic component according to claim 5, wherein the surface roughness of the intermediate portion is rougher than the surface roughness of the end portion.

[9] A ceramic electronic component in which external electrodes formed using a conductive paste are provided at both ends of a ceramic laminate incorporating an electronic element,

The ceramic laminate includes a main portion and an end portion provided with the external electrode, and the end portion is located on the inner side of the outer periphery of the main portion in plan view from the arrangement direction of the main portion and the end portion. Formed into

The external electrode is formed on the surface of the end portion up to a boundary portion with a main portion.

[10] A ceramic electronic component provided with external electrodes formed using a conductive paste on both ends of a ceramic laminate incorporating an electronic element,

The intermediate portion is provided in a concave shape between the main portion and the end portion,

The external electrode is formed on the surface of the end portion up to a boundary portion with the intermediate portion or the main portion;

Ceramic electronic parts characterized by

[11] A ceramic electronic component provided with external electrodes formed using a conductive paste on both ends of a ceramic laminate incorporating an electronic element,

The intermediate portion is provided in a convex shape between the main portion and the end portion,

The external electrode is formed on the surface of the end portion up to a boundary portion with the intermediate portion;

Ceramic electronic parts characterized by

[12] Formed using conductive paste on both ends of ceramic laminate with built-in electronic elements A method of manufacturing a ceramic electronic component provided with an external electrode,

The ceramic sheets are laminated to form a laminate composed of a main part having a surface state with relatively low wettability of the conductive paste and an end having a surface state with relatively high wettability of the conductive paste. Process,

Applying a conductive paste to the surface of the end to form an external electrode up to the boundary with the main part;

A method of manufacturing a ceramic electronic component comprising:

[13] A method for producing a ceramic electronic component comprising external electrodes formed using a conductive paste on both ends of a ceramic laminate incorporating an electronic element,

Laminating ceramic sheets, the main part, the end part having a surface state with relatively high wettability of the conductive paste, the conductive part having relatively low wettability and the surface state having the surface part and the main part A step of forming a laminate comprising an intermediate portion located between the end portions, a step of applying a conductive paste to the surface of the end portion and forming an external electrode up to the boundary portion with the intermediate portion;

A method of manufacturing a ceramic electronic component comprising:

[14] The main part or the intermediate part having a surface state in which the wettability of the conductive paste is relatively low is formed by producing a ceramic green sheet and laminating the ceramic raw material power including a burned material. 14. The method of manufacturing a ceramic electronic component according to claim 12, wherein the ceramic electronic component is manufactured according to claim 12.

[15] A method for producing a ceramic electronic component comprising external electrodes formed using a conductive paste at both ends of a ceramic laminate incorporating an electronic element,

A ceramic sheet is laminated, and consists of a main part and ends located at both ends of the main part. The main part and the arrangement direction of the end part are viewed in plan view, and the end part is inside the outer periphery of the main part. A process of forming a stacked body

A method of manufacturing a ceramic electronic component comprising:

[16] Formed using conductive paste on both ends of ceramic laminate with built-in electronic elements A method of manufacturing a ceramic electronic component provided with an external electrode,

The ceramic sheet is laminated and consists of a main part, an end part, and an intermediate part located between the main part and the end part, and the surface shape of the intermediate part is different from the surface shape of the main part and the end part. Forming a laminate on

A conductive paste is applied to the surface of the end portion to connect the external electrode to the intermediate portion or the main portion.

Forming to the boundary part;

A method of manufacturing a ceramic electronic component comprising:

17. The method for manufacturing a ceramic electronic component according to claim 16, wherein the surface shape of the intermediate portion is formed concave or convex with respect to the main portion and the end portion.

[18] The manufacturing of the ceramic electronic component according to any one of [12] to [17], wherein the external electrode is formed by immersing an end of the laminate in a conductive paste. Method.