JP2022154895A - Ceramic electronic component and manufacturing method thereof - Google Patents

Abstract

To make it possible to suppress characteristic change of a ceramic electronic component and discriminate the start and end of lamination.SOLUTION: A ceramic electronic component comprises a lamination structure in which a dielectric layer consisting primarily of ceramic and an internal electrode layer are alternately laminated, a first cover layer provided on a surface in one end in a lamination direction of the lamination structure and consisting primarily of ceramic, and a second cover layer provided on a surface in the other end in the lamination direction of the lamination structure. The same additive element whose concentration to a main-component ceramic is 1 mol% or less is added to the first cover layer and the second cover layer or the same additive element whose concentration to the main-component ceramic is 1 mol% or less is added to only any of the first cover layer and the second cover layer, A concentration difference of the additive element between the first cover layer and the second cover layer is twice or more of a standard deviation when measured by a minor surface part-microanalysis device five times or more.SELECTED DRAWING: Figure 1

Description

The present invention relates to ceramic electronic components and methods of manufacturing the same.

In recent years, with the increasing density of electronic circuits used in digital electronic devices such as mobile phones and tablet terminals, there is a strong demand for miniaturization of electronic components. And capacity is rapidly increasing (see, for example, Patent Documents 1 and 2).

JP 2014-022722 A JP 2016-162868 A

For ceramic electronic components with thin dielectric layers, defects due to the lamination process can occur. Defects occur at different probabilities near the start of lamination and near the end of lamination due to the process using lamination and pressure bonding. If the dielectric layer is thin, the size of the defect of interest will also be smaller, so it will take longer to find the defect. If it is possible to determine whether it is the beginning side or the end side of lamination, the labor and time required for analysis can be greatly reduced.

Therefore, by fabricating ceramic electronic components with a structure that allows easy identification of the start and end of lamination, it is possible to easily identify defects during manufacturing when the need for failure analysis arises. As a result, the yield can be improved.

For example, Patent Literature 1 discloses a technique for making upper and lower cover layers different in thickness. However, in this method, one of the cover layers has to be thickened, which has the disadvantage of lowering the capacity of the ceramic electronic component, which is required to have as high a capacity as possible within a limited dimension.

Therefore, it is conceivable to add a dye component to one of the cover layers using the technique of Patent Document 2. However, there is a concern that a large amount of dye component diffuses into the dielectric layer and deteriorates the insulation resistance. For example, an additive that colors the Ti oxide or Zr oxide used in the dielectric layer acts as a donor in the perovskite oxide and increases the concentration of carriers that contribute to electrical conduction.

SUMMARY OF THE INVENTION It is an object of the present invention to determine the start and end of lamination while suppressing changes in the characteristics of ceramic electronic components.

A ceramic electronic component according to the present invention comprises a laminated structure in which dielectric layers containing ceramic as a main component and internal electrode layers are alternately laminated; a first cover layer containing ceramic as a main component; and a second cover layer containing ceramic as a main component, provided on the surface of the other end in the stacking direction of the laminated structure, wherein the first cover layer and Either the same additive element is added to the second cover layer at a concentration of 1 mol % or less relative to the main component ceramic, or only one of the first cover layer and the second cover layer has a concentration relative to the main component ceramic is 1 mol % or less of the additive element, and the difference in concentration of the additive element between the first cover layer and the second cover layer is measured at least 5 times with a surface microanalyzer/microanalyzer. It is characterized by being twice or more the standard deviation when

In the above ceramic electronic component, the concentration of the additive element, whichever is larger, out of the concentration of the additive element in the first cover layer and the concentration of the additive element in the second cover layer, may be 0.001 mol % or more. good.

In the above ceramic electronic component, the ratio of the concentration difference of the additive element to the concentration of the additive element, whichever is larger, out of the concentration of the additive element in the first cover layer and the concentration of the additive element in the second cover layer, is It may be 5% or more.

In the ceramic electronic component described above, the main component ceramic of the dielectric layer may have a perovskite structure.

In the above ceramic electronic component, the additive element may be a metal element.

A method for manufacturing a ceramic electronic component according to the present invention includes: a laminated portion in which a dielectric green sheet containing a main component ceramic powder and a pattern of a metallic conductive paste are laminated; A ceramic laminate is prepared which includes a first cover sheet arranged on one end surface and a second cover sheet containing a main component ceramic powder and arranged on the other end surface in the lamination direction of the laminated portion. and firing the ceramic laminate, wherein the same additive element is added to the first cover sheet and the second cover sheet before firing, or the same additive element is added to the first cover sheet and the second cover sheet before firing. The additive element is added to only one of the cover sheets, and the additive element is added to the first cover layer obtained by firing the first cover sheet and the second cover layer obtained by firing the second cover sheet. is 1 mol% or less with respect to the main component ceramic, and the concentration difference of the additive element between the first cover layer and the second cover layer is 5 times with a surface micro-part/microanalyzer The ceramic laminate is sintered so that the standard deviation is at least twice the standard deviation of the above measurements.

According to the present invention, it is possible to determine the start and end of lamination while suppressing changes in the characteristics of the ceramic electronic component.

1 is a partial cross-sectional perspective view of a laminated ceramic capacitor; FIG. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1; FIG. 2 is a cross-sectional view taken along line BB of FIG. 1; It is a figure which illustrates the flow of the manufacturing method of a laminated ceramic capacitor. (a) and (b) are figures which illustrate a lamination process. It is a figure which illustrates a lamination process.

Hereinafter, embodiments will be described with reference to the drawings.

(embodiment)
FIG. 1 is a partial cross-sectional perspective view of a laminated ceramic capacitor 100 according to an embodiment. FIG. 2 is a cross-sectional view taken along line AA of FIG. 3 is a cross-sectional view taken along line BB of FIG. 1. FIG. As illustrated in FIGS. 1 to 3, a multilayer ceramic capacitor 100 includes a multilayer chip 10 having a substantially rectangular parallelepiped shape, and external electrodes 20a and 20b provided on either of the two opposing end surfaces of the multilayer chip 10. . Of the four surfaces of the laminated chip 10 other than the two end surfaces, two surfaces other than the top surface and the bottom surface in the stacking direction are referred to as side surfaces. The external electrodes 20a and 20b extend on the upper surface, lower surface and two side surfaces of the laminated chip 10 in the lamination direction. However, the external electrodes 20a and 20b are separated from each other.

A laminated chip 10 has a structure in which dielectric layers 11 containing a ceramic material functioning as a dielectric and internal electrode layers 12 containing a base metal material are alternately laminated. The edge of each internal electrode layer 12 is alternately exposed to the end face provided with the external electrode 20a of the laminated chip 10 and the end face provided with the external electrode 20b. Thereby, each internal electrode layer 12 is alternately connected to the external electrode 20a and the external electrode 20b. As a result, the multilayer ceramic capacitor 100 has a configuration in which a plurality of dielectric layers 11 are laminated with internal electrode layers 12 interposed therebetween. In the laminated body of the dielectric layers 11 and the internal electrode layers 12, the internal electrode layer 12 is arranged as the outermost layer in the lamination direction, and the lower surface of the laminated body is covered with the first cover layer 13a. The upper surface of the laminate is covered with a second cover layer 13b. The first cover layer 13a and the second cover layer 13b are mainly composed of a ceramic material. For example, the materials of the first cover layer 13a and the second cover layer 13b are the same as the main component of the dielectric layer 11 and the ceramic material.

The size of the multilayer ceramic capacitor 100 is, for example, length 0.25 mm, width 0.125 mm, and height 0.125 mm, or length 0.4 mm, width 0.2 mm, height 0.2 mm, or length 0.6 mm, 0.3 mm wide and 0.3 mm high; or 1.0 mm long, 0.5 mm wide and 0.5 mm high; or 3.2 mm long, 1.6 mm wide and 0.5 mm high. 1.6 mm in height, or 4.5 mm in length, 3.2 mm in width and 2.5 mm in height, but are not limited to these sizes.

The internal electrode layers 12 are mainly composed of base metals such as Ni (nickel), Cu (copper), and Sn (tin). As the internal electrode layers 12, noble metals such as Pt (platinum), Pd (palladium), Ag (silver), Au (gold), and alloys containing these may be used. The dielectric layer 11 is mainly composed of, for example, a ceramic material having a perovskite structure represented by the general formula _ABO3 . Note that the perovskite structure contains ABO _3-α deviating from the stoichiometric composition. For example, the ceramic material includes BaTiO ₃ (barium titanate), BaZrO ₃ (barium zirconate), CaZrO ₃ (calcium zirconate), CaTiO ₃ (calcium titanate), SrTiO ₃ (strontium titanate), and a perovskite structure. Formed Ba _1-xy Ca _x Sr _y Ti _1-z Zr _z O ₃ (0≦x≦1, 0≦y≦1, 0≦z≦1) and the like can be used.

The average thickness of each internal electrode layer 12 is, for example, 1.5 μm or less, 1.0 μm or less, or 0.7 μm or less. The average thickness of each dielectric layer 11 is, for example, 5.0 μm or less, 3.0 μm or less, or 1.0 μm or less.

As illustrated in FIG. 2, the area where the internal electrode layer 12 connected to the external electrode 20a and the internal electrode layer 12 connected to the external electrode 20b face each other is the area that produces the capacitance in the multilayer ceramic capacitor 100. . Therefore, a region that produces the electric capacitance is called a capacitance region 14 . That is, the capacitance region 14 is a region where adjacent internal electrode layers 12 connected to different external electrodes face each other.

A region in which the internal electrode layers 12 connected to the external electrode 20a face each other without interposing the internal electrode layers 12 connected to the external electrode 20b is called an end margin 15 . The end margin 15 is also a region where the internal electrode layers 12 connected to the external electrode 20b face each other without interposing the internal electrode layers 12 connected to the external electrode 20a. That is, the end margin 15 is a region where the internal electrode layers 12 connected to the same external electrode face each other without interposing the internal electrode layers 12 connected to different external electrodes. The end margin 15 is a region that does not produce capacitance.

As exemplified in FIG. 3 , in the laminated chip 10 , regions from two side surfaces of the laminated chip 10 to the internal electrode layers 12 are called side margins 16 . That is, the side margin 16 is a region provided so as to cover the end portions of the plurality of internal electrode layers 12 laminated in the laminated structure extending to the two side surfaces. The side margin 16 is also a region that does not generate capacitance.

The multilayer ceramic capacitor 100 is obtained by stacking powdery sheets corresponding to each layer, compressing them, and firing them. For example, on a cover sheet for the first cover layer 13a, a plurality of dielectric green sheets for the dielectric layer 11 on which electrode patterns for the internal electrode layers 12 are printed are laminated, and then a dielectric green sheet for the second cover layer 13b is laminated thereon. The cover sheets are laminated, pressed, and then fired.

During the lamination or crimping process, defects resulting from the lamination process may occur. Defects occur at different probabilities near the start of lamination and near the end of lamination due to the process using lamination and pressure bonding. When the dielectric layer 11 is thinned, the size of problematic defects is also smaller, so finding the defects takes longer. However, if it is possible to determine whether the two cover layers of the multilayer ceramic capacitor are the first cover layer 13a at the start of lamination or the second cover layer 13b at the end of lamination, taking into account the different defect rates described above, The labor and time required for analysis can be greatly reduced. Therefore, by manufacturing a multilayer ceramic capacitor with a structure that allows easy identification of the two cover layers, it is possible to easily identify defects during manufacturing when the need for failure analysis arises. As a result, the yield can be improved.

Therefore, for example, by making the thickness of the first cover layer 13a and the thickness of the second cover layer 13b different so that the difference in thickness can be confirmed, the first cover layer 13a and the second cover layer 13b can be distinguished. can be considered. However, in this method, one of the cover layers must be thickened, resulting in the disadvantage of lowering the capacity of the multilayer ceramic capacitor, which is required to have as high a capacity as possible within limited dimensions.

Therefore, it is conceivable to add a pigment component to one of the first cover layer 13a and the second cover layer 13b. However, if a large amount of dye component diffuses into the dielectric layer 11, there is a concern that the insulation resistance will be deteriorated. For example, an additive that colors the Ti oxide or Zr oxide used in the dielectric layer 11 may act as a donor in the perovskite oxide and increase the concentration of carriers that contribute to electrical conduction.

Therefore, the multilayer ceramic capacitor 100 according to the present embodiment has a configuration capable of distinguishing between the first cover layer 13a at the start of lamination and the second cover layer 13b at the end of lamination while suppressing changes in characteristics. there is

Specifically, a small amount of common additive element is added to the first cover layer 13a and the second cover layer 13b to the extent that changes in the characteristics of the multilayer ceramic capacitor 100 are suppressed. For example, the amount of the common additive element added is specified so that good insulation is maintained. Next, between the first cover layer 13a and the second cover layer 13b, a common density difference is detected between the first cover layer 13a and the second cover layer 13b so that a density difference is detected to the extent that it is not a measurement error. The additive element has a concentration difference. It is determined in advance which one of the cover sheets at the start of stacking and the cover sheet at the end of stacking to have a higher common additive element concentration. It becomes possible to distinguish from the second cover layer 13b.

More specifically, one of the first cover layer 13a and the second cover layer 13b has a common additive element concentration of 1 mol % or less when the main component ceramic is 100 mol %. The common additive element is not added to the other cover layer, or the common additive element is added so as to have a lower concentration than the one cover layer. As a result, in the first cover layer 13a and the second cover layer 13b, the common additive element concentration is 1 mol % or less when the main component ceramic is 100 mol %. Therefore, even if the common additive element diffuses into the dielectric layer 11 and acts as a donor, acceptor, or additive for the main component ceramic of the dielectric layer 11, the effect on the properties of the dielectric layer 11 is limited. Therefore, changes in the characteristics of the multilayer ceramic capacitor 100 can be suppressed.

Next, the common additive element concentration difference between the first cover layer 13a and the second cover layer 13b is measured by LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry), μ-XRF (micro-region fluorescence X-ray analysis), SIMS (secondary ion mass spectrometry), EPMA (electron probe microanalyzer), etc., and the standard deviation should be at least twice the standard deviation when measured 5 times or more with surface microanalysis / microanalysis equipment. Keep As a result, it is possible to detect which of the concentration of the common additive element in the first cover layer 13a and the concentration of the common additive element in the second cover layer 13b is higher while suppressing the influence of measurement errors. Become. Therefore, it is possible to distinguish between the first cover layer 13a at the start of lamination and the second cover layer 13b at the end of lamination.

Regarding the concentration difference measurement of the common additive element, for one sample, the common additive element concentration in the first cover layer 13a was measured five times, and then the common additive element concentration in the second cover layer 13b was measured five times. , the difference in concentration of the common additive element can be obtained by subtracting the respective average values. The standard deviation of this concentration difference can be obtained by squaring the standard deviations of common additive element concentrations on each of the front and back surfaces measured five times, taking the sum, and taking the square root. When the standard deviation of the density difference thus measured is measured, each measured density difference is at least twice the standard deviation.

Conventionally, each cover layer was identified by polishing the multilayer ceramic capacitor over several hours and observing and identifying the internal structure. On the other hand, in the multilayer ceramic capacitor 100 according to the present embodiment, it is possible to perform measurement at a high speed of about 10 msec by using a surface micropart/microanalyzer such as the LA-ICP-MS described above. . As a result, the efficiency of defect analysis is improved, and the product yield can be efficiently increased. Further, when the dielectric layer 11 becomes thinner, it is necessary to perform polishing with less polishing marks. It becomes possible to distinguish between the first cover layer 13a and the second cover layer 13b regardless of the thickness.

Note that the common additive element added to the first cover layer 13a and the second cover layer 13b can be measured by a surface microanalysis/microanalyzer such as LA-ICP-MS, and is used for the multilayer ceramic capacitor to be applied. Any element may be used as long as it is not used as a main element (here, the main element is an element added at a concentration of 1 mol % or more). For example, a metal element or the like can be used. A halogen element or the like can also be used if evaporation can be suppressed during the baking process.

Also, two or more common additive elements may be added to the first cover layer 13a and the second cover layer 13b. The first cover layer 13a and the second cover layer 13b can be distinguished from each other by providing a concentration difference for each common additive element and measuring the concentration difference of each common additive element. Since the measurement results of the additive element concentration difference of two or more types can be used, the measurement accuracy is improved.

If the main component ceramics of the first cover layer 13a and the second cover layer 13b have a perovskite structure, the additive element concentration is 100 mol % of the B-site element of the main component ceramic. That is. For example, if the main component ceramic is barium titanate, the additive element concentration is mol % when titanium is 100 mol %.

If the common additive element concentration in the first cover layer 13a and the second cover layer 13b is high, the characteristics of the multilayer ceramic capacitor 100 may change significantly. In this embodiment, the common additive element concentration in the first cover layer 13a and the second cover layer 13b is preferably 0.1 mol % or less, more preferably 0.05 mol % or less.

On the other hand, if the larger one of the common additive element concentration of the first cover layer 13a and the common additive element concentration of the second cover layer 13b is too low, the common additive element concentration cannot be measured with high accuracy. There is a risk. Therefore, it is preferable to set a lower limit to the higher common additive element concentration. In the present embodiment, the concentration of the larger common additive element is preferably 0.001 mol % or more, more preferably 0.01 mol % or more.

If the common additive element concentration difference between the first cover layer 13a and the second cover layer 13b is small, high measurement accuracy may not be obtained. Therefore, it is preferable to set a lower limit for the common additive element concentration difference. For example, the common additive element concentration difference is preferably three times or more the standard deviation, more preferably six times or more, and even more preferably ten times or more.

If the difference in concentration of the common additive element is small with respect to the common additive element concentration of the common additive element concentration of the first cover layer 13a and the common additive element concentration of the second cover layer 13b, whichever is larger, the concentration difference cannot be detected. There is a risk. Therefore, it is preferable to set a lower limit for the ratio of the common additive element concentration difference to the larger common additive element concentration. For example, the ratio is preferably 5% or more, more preferably 10% or more, and even more preferably 15% or more.

Next, a method for manufacturing the laminated ceramic capacitor 100 will be described. FIG. 4 is a diagram illustrating the flow of the manufacturing method of the multilayer ceramic capacitor 100. As shown in FIG.

(Raw material powder preparation process)
The A-site and B-site elements contained in the dielectric layer 11 are usually contained in the dielectric layer 11 in the form of sintered particles of _ABO3 . For example, BaTiO ₃ is a tetragonal compound with a perovskite structure and exhibits a high dielectric constant. This BaTiO ₃ can generally be obtained by reacting a titanium raw material such as titanium dioxide with a barium raw material such as barium carbonate to synthesize barium titanate. Various methods are conventionally known for synthesizing the main component ceramic of the dielectric layer 11, such as a solid phase method, a sol-gel method, and a hydrothermal method. Any of these can be employed in the present embodiment.

A predetermined additive compound is added to the obtained ceramic powder according to the purpose. Additive compounds include Mg (magnesium), Mn (manganese), V (vanadium), Cr (chromium), rare earth elements (Y (yttrium), Sm (samarium), Eu (europium), Gd (gadolinium), Tb ( terbium), Dy (dysprosium), Ho (holmium), Er (erbium), Tm (thulium) and Yb (ytterbium)) oxides, as well as Co (cobalt), Ni (nickel), Li (lithium), B (boron), Na (sodium), K (potassium) and Si (silicon) oxides or glasses.

For example, a ceramic raw material powder is wet-mixed with a compound containing an additive compound, dried and pulverized to prepare a ceramic material. For example, the ceramic material obtained as described above may be pulverized to adjust the particle size, or combined with a classification process to adjust the particle size. A dielectric material is obtained by the above steps.

Next, cover materials for forming the first cover layer 13a and the second cover layer 13b are prepared. As the main component ceramic of the cover material, the same dielectric material as described above can be used. However, a concentration difference is provided in the common additive element between the cover material for the first cover layer 13a and the cover material for the second cover layer 13b.

(Lamination process)
Next, a binder such as polyvinyl butyral (PVB) resin, an organic solvent such as ethanol or toluene, and a plasticizer are added to the dielectric material and wet-mixed. Using the obtained slurry, the dielectric green sheet 51 is coated on the substrate by, for example, a die coater method or a doctor blade method, and dried. Also, a binder such as polyvinyl butyral (PVB) resin, an organic solvent such as ethanol or toluene, and a plasticizer are added to the cover material for the first cover layer 13a and wet-mixed. The obtained slurry is used to coat the first cover sheet 54a on the substrate by, for example, a die coater method or a doctor blade method, and dried. Also, a binder such as polyvinyl butyral (PVB) resin, an organic solvent such as ethanol or toluene, and a plasticizer are added to the cover material for the second cover layer 13b and wet-mixed. The obtained slurry is used to coat the second cover sheet 54b on the substrate by, for example, a die coater method or a doctor blade method, and dried.

Next, as exemplified in FIG. 5A, a metal conductive paste for forming internal electrodes containing an organic binder is printed on the surface of the dielectric green sheet 51 by screen printing, gravure printing, or the like to form internal electrodes. A first pattern 52 for the layer is laid down. Ceramic particles are added to the metal conductive paste as a common material. Although the main component of the ceramic particles is not particularly limited, it is preferably the same as the main component ceramic of the dielectric layer 11 . Next, on the dielectric green sheet 51, a reverse pattern paste is printed on the peripheral area where the first pattern 52 is not printed, thereby arranging the second pattern 53 and filling the step with the first pattern 52. The reverse pattern paste may have the same component as the dielectric green sheet 51, or may have a different additive compound.

Next, as illustrated in FIG. 6, a predetermined number (for example, 1 to 10 layers) of first cover sheets 54a are laminated. Next, as exemplified in FIG. 5B, the internal electrode layers 12 and the dielectric layers 11 are arranged alternately, and the internal electrode layers 12 are formed on both end faces in the length direction of the dielectric layer 11 . A dielectric green sheet 51, a first pattern 52 and a second pattern 53 are laminated such that the edges are alternately exposed and drawn out to the pair of external electrodes 20a and 20b having different polarities. For example, it is assumed that the dielectric green sheet 51 has 100 to 500 layers.

Next, as exemplified in FIG. 6, a predetermined number (for example, 1 to 10 layers) of second cover sheets 54b are laminated on the laminated dielectric green sheets 51 and thermally compressed to obtain a predetermined chip size (for example, 1.0 mm x 0.5 mm). After that, a metal conductive paste to be the external electrodes 20a and 20b is applied to both side surfaces of the cut laminate by a dipping method or the like and dried. A ceramic laminate is thus obtained.

(Baking process)
After removing the binder from the ceramic laminate thus obtained in an N ₂ atmosphere, a metal paste that serves as a base layer for the external electrodes 20a and 20b is applied by a dipping method, and the oxygen partial pressure is 10 ⁻¹² to 10 ⁻⁹ . Firing at 1100 to 1300° C. for 10 minutes to 2 hours in a reducing atmosphere of atm. Thus, the laminated ceramic capacitor 100 is obtained.

(Reoxidation treatment step)
After that, reoxidation treatment may be performed at 600° C. to 1000° C. in an N ₂ gas atmosphere.

(Plating process)
After that, metal coating such as Cu, Ni, and Sn is applied to the underlying layers of the external electrodes 20a and 20b by plating. Through the above steps, the multilayer ceramic capacitor 100 is completed.

In the manufacturing method according to the present embodiment, the common additive element is added to the first cover sheet 54a and the second cover sheet 54b before firing, or only one of the first cover sheet 54a and the second cover sheet 54b is added. The additive element is added in advance. Further, the concentration of the common additive element in the first cover layer 13a obtained by firing the first cover sheet 54a and the second cover layer 13b obtained by firing the second cover sheet 54b is 1 mol % or less with respect to the main component ceramic. and the common additive element concentration difference between the first cover layer 13a and the second cover layer 13b after firing is twice the standard deviation when measured five times or more with a surface micro-part/microanalyzer. A baking process is performed so that it may become above. According to this technique, it is possible to discriminate between the first cover layer 13a at the start of lamination and the second cover layer 13b at the end of lamination while suppressing changes in the characteristics of the multilayer ceramic capacitor 100 .

In addition, in each of the above-described embodiments, a laminated ceramic capacitor has been described as an example of a ceramic electronic component, but the present invention is not limited to this. For example, other electronic components such as varistors and thermistors may be used.

Hereinafter, multilayer ceramic capacitors according to the embodiments were produced and their characteristics were examined.

(Example 1)
Additives were added to the barium titanate powder, and the mixture was sufficiently wet-mixed and pulverized in a ball mill to obtain a dielectric material. Additives were added to the barium titanate powder, and the mixture was sufficiently wet-mixed and pulverized in a ball mill to obtain a cover material.

Sodium was added as an additive element to the cover material, and a binder such as polyvinyl butyral (PVB) resin, an organic solvent such as ethanol or toluene, and a plasticizer were added and wet-mixed. The resulting slurry was used to coat a first cover sheet onto a substrate and allowed to dry. In the first cover sheet, when Ti was 100 mol %, Na was 0.006 mol %.

Na was added as an additive element to the cover material, and a binder such as polyvinyl butyral (PVB) resin, an organic solvent such as ethanol or toluene, and a plasticizer were added and wet-mixed. The resulting slurry was used to coat a second cover sheet onto the substrate and allowed to dry. In the second cover sheet, when Ti was 100 mol %, Na was 0.009 mol %.

Without adding Na to the dielectric material, a binder such as polyvinyl butyral (PVB) resin, an organic solvent such as ethanol or toluene, and a plasticizer were added and wet-mixed. Using the obtained slurry, a dielectric green sheet was coated on a substrate and dried. An electrode pattern of a metallic conductive paste containing Ni as a main component metal was printed on the obtained dielectric green sheet.

The first cover sheet is peeled off from the base material to laminate 40 layers, the dielectric green sheet on which the electrode pattern is printed is peeled off from the base material, and 500 layers are laminated so that the electrode patterns are alternately shifted, and the second cover sheet is laminated. The sheet is peeled from the base material, laminated with 40 layers, crimped, cut into a predetermined shape, a metallic conductive paste containing Ni as a main component is applied to the two end faces where the electrode pattern is exposed, and fired in a reducing atmosphere. A sintered body was obtained. In these processes, a manufacturing process was used in which Na entering from the outside was sufficiently removed.

(Comparative example 1)
In Comparative Example 1, in the first cover sheet, when Ti was 100 mol %, Na was 0.007 mol %. In the second cover sheet, when Ti was 100 mol %, Na was 0.008 mol %. Other conditions were the same as in Example 1.

(Comparative example 2)
In Comparative Example 2, in the first cover sheet, when Ti was 100 mol %, Na was 0.006 mol %. In the second cover sheet, when Ti was 100 mol %, Na was 1.1 mol %. Other conditions were the same as in Example 1.

Is it possible to distinguish between the first cover layer obtained from the first cover sheet and the second cover layer obtained from the second cover sheet in each of Example 1, Comparative Example 1, and Comparative Example 2? , from the difference in composition quantitative analysis results by LA-ICP-MS. As the LA-ICP-MS apparatus, an apparatus obtained by connecting a laser ablation system NWR213 made by NWR/ESI to an ICP-MS apparatus Agilent 7900 made by Agilent was used. If the difference in the concentration of the common additive element between the first cover layer and the second cover layer is at least twice the standard deviation when measured five times or more, it is judged to be discriminable "OK". Otherwise, it was judged as "NG". Also, the quality of the characteristics as a multilayer ceramic capacitor was examined by measuring the insulation resistance. If the insulation resistance was 1 GΩ, it was determined that the insulation was good "OK", and if not, it was determined that the insulation was bad "NG". Table 1 shows the results.

In Comparative Example 1, the insulating property was determined to be "OK". This is probably because the additive element concentration was 1 mol % or less in any of the cover sheets. However, in Comparative Example 1, discrimination between the first cover layer and the second cover layer was judged to be "NG". This is probably because the concentration difference exceeding the measurement error was not provided in the measurement using LA-ICP-MS.

In Comparative Example 2, discrimination between the first cover layer and the second cover layer was judged to be "OK". It is considered that this is because the concentration difference larger than the measurement error was provided in the measurement using LA-ICP-MS. However, in Comparative Example 2, the insulation was determined to be "NG". It is believed that this is because the additive element concentration in the second cover sheet exceeded 1 mol %.

In comparison with these, in Example 1, discrimination between the first cover layer and the second cover layer was judged to be "OK". It is considered that this is because the concentration difference larger than the measurement error was provided in the measurement using LA-ICP-MS. Next, in Example 1, it was determined that the insulation was good and "OK". This is probably because the additive element concentration was 1 mol % or less in any of the cover sheets.

(Example 2)
In Example 2, Sn was used instead of Na as the additive element. No Sn was added to the first cover sheet. That is, in the first cover sheet, when Ti was 100 mol %, Sn was 0.000 mol %. In the second cover sheet, when Ti was 100 mol %, Sn was 0.017 mol %. Other conditions were the same as in Example 1.

(Example 3)
In Example 3, Re (rhenium) was used as the additive element instead of Na. No Re was added to the first cover sheet. That is, in the first cover sheet, when Ti is 100 mol %, Re is 0.00000 mol %. In the second cover sheet, when Ti was 100 mol %, Re was 0.33284 mol %. Other conditions were the same as in Example 1.

(Example 4)
In Example 4, Ag was used as an additive element without using Na. No Ag was added to the first cover sheet. That is, in the first cover sheet, when Ti was 100 mol %, Ag was 0.0000 mol %. In the second cover sheet, when Ti was 100 mol %, Ag was 0.0030 mol %. Other conditions were the same as in Example 1.

(Example 5)
In Example 5, Bi (bismuth) was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Bi was 0.00006 mol %. In the second cover sheet, when Ti was 100 mol %, Bi was 0.00017 mol %. Other conditions were the same as in Example 1.

(Example 6)
In Example 6, Au was used as an additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Au was 0.00001 mol %. In the second cover sheet, when Ti was 100 mol %, Au was 0.00879 mol %. Other conditions were the same as in Example 1.

(Example 7)
In Example 7, Zn (zinc) was used as the additive element instead of Na. In the first cover sheet, Zn was 0.0185 mol % when Ti was 100 mol %. In the second cover sheet, Zn was 0.0599 mol % when Ti was 100 mol %. Other conditions were the same as in Example 1.

(Example 8)
In Example 8, Pt was used instead of Na as the additive element. In the first cover sheet, when Ti was 100 mol %, Pt was 0.0017 mol %. In the second cover sheet, when Ti was 100 mol %, Pt was 0.0072 mol %. Other conditions were the same as in Example 1.

For each of Examples 2 to 8, the same tests and the same criteria as in Example 1 and Comparative Examples 1 and 2 were used to determine whether it was possible to distinguish between the first cover layer and the second cover layer. , to determine whether the insulation is good. Table 2 shows the results. In Examples 2 to 8 as well, it was determined that discrimination between the first cover layer and the second cover layer was possible and "OK". It is considered that this is because the concentration difference larger than the measurement error was provided in the measurement using LA-ICP-MS. In addition, it was determined that the insulation was good "OK". This is probably because the additive element concentration was 1 mol % or less in any of the cover sheets.

(Example 9)
In Example 9, in the first cover sheet, when Ti was 100 mol %, Na was 0.006 mol %. In the second cover sheet, when Ti was 100 mol %, Na was 0.025 mol %. Other conditions were the same as in Example 1.

(Example 10)
In Example 10, Dy was used as an additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Dy was 0.53 mol %. In the second cover sheet, when Ti was 100 mol %, Dy was 0.76 mol %. Other conditions were the same as in Example 1.

(Example 11)
In Example 11, W (tungsten) was used as the additive element instead of Na. In the first cover sheet, W was 0.0010 mol % when Ti was 100 mol %. In the second cover sheet, W was 0.0044 mol % when Ti was 100 mol %. Other conditions were the same as in Example 1.

(Example 12)
In Example 12, Mn was used as an additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Mn was 0.13 mol %. In the second cover sheet, when Ti was 100 mol %, Mn was 0.17 mol %. Other conditions were the same as in Example 1.

(Example 13)
In Example 13, V was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, V was 0.07 mol %. In the second cover sheet, when Ti was 100 mol %, V was 0.11 mol %. Other conditions were the same as in Example 1.

(Example 14)
In Example 14, Mg was used as an additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Mg was 0.05 mol %. In the second cover sheet, when Ti was 100 mol %, Mg was 0.07 mol %. Other conditions were the same as in Example 1.

(Example 15)
In Example 15, Mo (molybdenum) was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Mo was 0.02 mol %. In the second cover sheet, when Ti was 100 mol %, Mo was 0.13 mol %. Other conditions were the same as in Example 1.

(Example 16)
In Example 16, Si was used instead of Na as the additive element. In the first cover sheet, when Ti was 100 mol %, Si was 0.14 mol %. In the second cover sheet, when Ti was 100 mol %, Si was 0.22 mol %. Other conditions were the same as in Example 1.

(Example 17)
In Example 17, B was used as an additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, B was 0.018 mol %. In the second cover sheet, when Ti was 100 mol %, B was 0.025 mol %. Other conditions were the same as in Example 1.

(Example 18)
In Example 18, Ni was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Ni was 0.25 mol %. In the second cover sheet, when Ti was 100 mol %, Ni was 0.54 mol %. Other conditions were the same as in Example 1.

(Example 19)
In Example 19, Zr (zirconium) was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Zr was 0.23 mol %. In the second cover sheet, when Ti was 100 mol %, Zr was 0.44 mol %. Other conditions were the same as in Example 1.

(Example 20)
In Example 20, Al (aluminum) was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Al was 0.010 mol %. In the second cover sheet, when Ti was 100 mol %, Al was 0.133 mol %. Other conditions were the same as in Example 1.

(Example 21)
In Example 21, Y was used as an additive element without using Na. In the first cover sheet, when Ti was 100 mol %, Y was 0.012 mol %. In the second cover sheet, when Ti was 100 mol %, Y was 0.030 mol %. Other conditions were the same as in Example 1.

(Example 22)
In Example 22, Sr (strontium) was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Sr was 0.011 mol %. In the second cover sheet, when Ti was 100 mol %, Sr was 0.015 mol %. Other conditions were the same as in Example 1.

(Example 23)
In Example 23, Hf (hafnium) was used as the additive element instead of Na. In the first cover sheet, when Ti was 100 mol %, Hf was 0.0029 mol %. In the second cover sheet, when Ti was 100 mol %, Hf was 0.0056 mol %. Other conditions were the same as in Example 1.

For each of Examples 9 to 23, the same tests and the same criteria as in Example 1 and Comparative Examples 1 and 2 were used to determine whether it was possible to distinguish between the first cover layer and the second cover layer. , to determine whether the insulation is good. Table 3 shows the results. In Examples 9 to 23 as well, it was determined that discrimination between the first cover layer and the second cover layer was possible and "OK". It is considered that this is because the concentration difference larger than the measurement error was provided in the measurement using LA-ICP-MS. In addition, it was determined that the insulation was good "OK". This is probably because the additive element concentration was 1 mol % or less in any of the cover sheets.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and variations can be made within the scope of the gist of the present invention described in the scope of claims. Change is possible.

REFERENCE SIGNS LIST 10 laminated chip 11 dielectric layer 12 internal electrode layer 13 cover layer 14 capacitance region 15 end margin 16 side margin 20a, 20b external electrode 100 laminated ceramic capacitor

Claims (6)

a laminated structure in which dielectric layers containing ceramic as a main component and internal electrode layers are alternately laminated;
a first cover layer provided on one end surface of the laminated structure in the lamination direction and containing ceramic as a main component;
a second cover layer provided on the surface of the other end in the lamination direction of the laminated structure and containing ceramic as a main component;
Either the same additive element is added to the first cover layer and the second cover layer at a concentration of 1 mol % or less relative to the main component ceramic, or only one of the first cover layer and the second cover layer is added. The additive element is added at a concentration of 1 mol% or less with respect to the main component ceramic,
The difference in concentration of the additive element between the first cover layer and the second cover layer is at least twice the standard deviation when measured five times or more with a surface microanalyzer/microanalyzer. ceramic electronic components. 2. The concentration of the additive element, which is larger of the concentration of the additive element in the first cover layer and the concentration of the additive element in the second cover layer, is 0.001 mol % or more. The ceramic electronic component according to . The ratio of the difference in concentration of the additive element to the concentration of the additive element, whichever is greater among the concentration of the additive element in the first cover layer and the concentration of the additive element in the second cover layer, is 5% or more. 3. The ceramic electronic component according to claim 1 or 2, characterized by: 4. The ceramic electronic component according to claim 1, wherein the main component ceramic of said dielectric layer has a perovskite structure. 5. The ceramic electronic component according to claim 1, wherein said additive element is a metal element. A laminated portion in which a dielectric green sheet containing a main component ceramic powder and a pattern of a metal conductive paste are laminated, and a first cover containing the main component ceramic powder and disposed on one end surface of the laminated portion in the lamination direction. a step of preparing a ceramic laminate comprising a sheet and a second cover sheet containing ceramic powder as a main component and arranged on the surface of the other end of the laminate portion in the lamination direction;
and firing the ceramic laminate,
The same additive element is added to the first cover sheet and the second cover sheet before firing, or the additive element is added to only one of the first cover sheet and the second cover sheet. ,
The concentration of the additive element in the first cover layer obtained by firing the first cover sheet and the second cover layer obtained by firing the second cover sheet is 1 mol % or less with respect to the main component ceramic, The concentration difference of the additive element between the first cover layer and the second cover layer is at least twice the standard deviation when measured five times or more with a surface microanalyzer/microanalyzer. A method of manufacturing a ceramic electronic component, comprising firing a ceramic laminate.

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