Conductive material, ceramic electronic component, and method for manufacturing same

Abstract

Provided is a technique whereby a conductor film provided on the surface of a ceramic electronic component is not susceptible to poor plating adhesion even if the conductor film is thinned, and a moisture penetration path can be formed. For example, in order to form external electrodes (6, 7) of a multilayer ceramic capacitor (1), a conductive material is prepared that contains CuO nanoparticles that become metallic copper as a conductive component by firing, a glass raw material mixture that becomes glass by firing, and a solvent that dissolves or disperses the CuO nanoparticles and the glass raw material mixture. The glass raw material mixture contains a metal salt in a powder state having a particle diameter of 100 nm or less or a metal salt in an ionic form, and the conductive material is applied to the surface of the ceramic body (2) and then fired at a temperature equal to or higher than the melting point of the glass raw material mixture to form external electrodes (6, 7).

Description

Technical Field

[0001] The present invention relates to a conductive material, a method for manufacturing a ceramic electronic component using the conductive material, and a ceramic electronic component obtained by the manufacturing method. Background Art

[0002] As a conductive material of interest for the present invention, for example, there is a conductor paste for a terminal electrode of a multilayer ceramic component described in Japanese Patent Application Laid-Open No. 2007-103845 (Patent Document 1). This conductor paste contains a conductive powder such as copper powder, a glass powder, and an organic carrier. Here, as the glass powder, by using a powder whose acid resistance is improved by composition adjustment, even if the terminal electrode of the multilayer ceramic component is a thin film, defects caused by penetration of the plating solution are less likely to occur, for example, a decrease in the adhesion strength of the terminal electrode to the body of the multilayer ceramic component, peeling of the terminal electrode, and the like.

[0003] In addition, in the case of the thin film of the terminal electrode envisioned in Patent Document 1, the film thickness is about 20 μm as described in paragraph 0006. Further, the particle size of the glass powder in the examples of Patent Document 1 is 3.3 μm as described in paragraph 0034.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2007-103845 Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] In addition to containing a conductive metal component, the terminal electrode of the multilayer ceramic component needs to contain glass in order to ensure the denseness of the film and the fixing property to the body. The glass powder in the conductor paste is used to provide this glass. The glass powders are fused to each other during firing for obtaining the multilayer ceramic component.

[0009] Regarding the terminal electrode, for example, when aiming for thinning to a film thickness of 5 μm or less, due to the fusion of the glass powders, the glass is significantly exposed on the surface of the external electrode, and the continuity of the distribution region of the conductive metal is reduced. As a result, poor plating adhesion may occur in the plating process performed on the terminal electrode. Further, when the glass penetrates in the thickness direction of the film of the terminal electrode, sometimes a moisture intrusion path may be formed in the terminal electrode because the glass is soluble in water.

[0010] Accordingly, an object of the present invention is to provide a technique that, even when a conductor film such as a terminal electrode provided on the surface of a ceramic electronic component is thinned, is less likely to cause poor plating adhesion and formation of a moisture intrusion path as described above.

[0011] Technical Solution for Solving the Problem

[0012] In the present invention, in order to solve the above technical problems, there are provided a conductive material for forming a conductor film that can meet requirements such as being less likely to cause poor plating adhesion and formation of a moisture intrusion path, and a manufacturing method of a ceramic electronic component that performs a conductor film forming process using the conductive material. Further, there is provided a ceramic electronic component obtained by the manufacturing method.

[0013] The conductive material according to the present invention is for forming a conductor film by firing, and is characterized in that the conductive material contains: nano CuO particles that become metallic copper as a conductive component by firing, a glass raw material mixture that becomes glass by firing, and a solvent that dissolves or disperses the nano CuO particles and the glass raw material mixture, and the glass raw material mixture contains a metal salt in a powder state having a particle size of 100 nm or less or a metal salt in an ionic form.

[0014] In addition, the present invention also relates to a manufacturing method of a ceramic electronic component including a ceramic body and a conductor film provided on the surface of the ceramic body. The manufacturing method according to the present invention is characterized by including: a step of providing the above conductive material to the surface of the ceramic body in order to form a conductor film; next, a step of heating and drying the glass raw material mixture contained in the conductive material; and next, a step of firing at a temperature equal to or higher than the melting point of the glass raw material mixture to form a conductor film.

[0015] Furthermore, the present invention also relates to a structure of a ceramic electronic component including a ceramic body and a conductor film provided on the surface of the ceramic body. The ceramic electronic component according to the present invention has the following characteristics.

[0016] The conductor film contains copper and glass. When observing a cross-section of the conductor film along the thickness direction, there are a plurality of glass domains including glass that are not in contact with either the surface or the substrate in the cross-section and are surrounded by copper. Moreover, it is characterized in that the average of the diameters of the circles surrounding the glass domains is 0.5 μm or more and 0.7 μm or less, the standard deviation of the diameters of the circles is 0.3 μm or more and 0.5 μm or less, and the ratio of the maximum diameter of the circle to the dimension in the thickness direction of the conductor film is less than 1.

[0017] Advantages of the Invention

[0018] According to the present invention, it is possible to obtain a ceramic electronic component having a conductor film that is less likely to cause poor plating adhesion and formation of a moisture intrusion path.

[0019] More specifically, according to the present invention, in order to form a conductor film, a conductive material containing nano-CuO particles as a conductive component and in which a glass raw material mixture contains a material in a powder state having a particle size of 100 nm or less or a material in an ionic form is used, and firing is performed at a temperature equal to or higher than the melting point of the glass raw material mixture to form a conductor film.

[0020] Therefore, in the firing process, when fusion of glasses occurs, copper and glass can each maintain a small state. As a result, a conductor film can be obtained in which, in a cross section along the thickness direction, the average diameter of a circle surrounded by glass that is not in contact with either the surface or the substrate and is surrounded by metal is 0.5 μm or more and 0.7 μm or less, the standard deviation of the circle diameter is 0.3 μm or more and 0.5 μm or less, and the ratio of the maximum diameter of the circle to the dimension in the thickness direction of the conductor film is less than 1.

[0021] In this conductor film, copper as a conductive component and the ceramic portion in the ceramic body are in a state joined by glass, and the glass is separated from the copper and is in a state of being dispersed in a small and uniform domain size. Therefore, ingress of moisture from the glass portion on the surface of the conductor film can be suppressed. In addition, significant exposure of glass on the surface of the conductor film is also suppressed, and good plating adhesion can be obtained. Description of the Drawings

[0022] Figure 1 is a schematic cross-sectional view showing a multilayer ceramic capacitor 1 which is a ceramic electronic component according to one embodiment of the present invention.

[0023] Figure 2 is a Figure 1 schematic cross-sectional view showing an enlarged part of a first external electrode 6 of the multilayer ceramic capacitor 1 shown.

[0024] Figure 3 is a view showing Figure 1 the cross-sectional structure of a conductor film employed as external electrodes 6 and 7 of the multilayer ceramic capacitor 1 shown, and is a view showing a SEM image of a cross section of a specimen of the conductor film 12 according to an example of the present invention taken in an experimental example.

[0025] Figure 4 is a view showing Figure 3 a further enlarged SEM image of a part of the conductor film 12 shown.

[0026] Figure 5 is a Figure 4 view in which a circle EC surrounding a glass domain 13 is marked in the SEM image shown.

[0027] Figure 6 This is a diagram showing a cross-sectional SEM image of a specimen of the conductor film 22 related to the comparative example taken in the experimental example. Detailed implementation mode

[0028] Refer to Figure 1 To describe the structure of the multilayer ceramic capacitor 1 as a ceramic electronic component according to an embodiment of the present invention.

[0029] The multilayer ceramic capacitor 1 includes a ceramic body 2. The ceramic body 2 includes a plurality of laminated ceramic layers 3, and a plurality of internal electrodes 4 and 5 disposed along the interfaces between the plurality of ceramic layers 3. The internal electrodes 4 and 5 are classified into a plurality of first internal electrodes 4 and a plurality of second internal electrodes 5 that are alternately disposed in the stacking direction of the ceramic body 2. On the surface of the ceramic body 2, more specifically, on the opposing end faces, a first external electrode 6 and a second external electrode 7 as conductor films are respectively provided. The first external electrode 6 is electrically connected to the first internal electrode 4, and the second external electrode 7 is electrically connected to the second internal electrode 5.

[0030] The ceramic layer 3 includes, for example, a dielectric ceramic having ABO 3 (A is at least one of Ba, Ca, and Sr, and B is at least one of Ti and Zr.) as a main component. In addition, the dielectric ceramic may have the above ABO 3 as a main component and contain at least one of Mn, Mg, Si, Y, Dy, and Gd as a sub-component.

[0031] The internal electrodes 4 and 5 preferably contain a conductive metal or an alloy containing a conductive metal. For example, it is preferable to contain one selected from nickel, copper, silver, and a silver / palladium alloy as a conductive component.

[0032] The external electrodes 6 and 7 are formed by applying the conductive material according to the present invention to the end faces of the ceramic body 2 so as to be in contact with the respective end portions of the internal electrodes 4 and 5, and after heating and drying the same, firing is performed.

[0033] The multilayer ceramic capacitor 1 is manufactured, for example, through the following steps. First, a ceramic slurry containing raw material powder of ceramic having the above-described composition is prepared. Next, an appropriate sheet forming method is applied to the ceramic slurry to form a green ceramic sheet. Next, on a given green ceramic sheet among the plurality of green ceramic sheets, a conductive paste to be the internal electrodes 4 and 5 is applied by printing or the like. Next, the plurality of green ceramic sheets are stacked and then pressed to obtain an unprocessed ceramic body. Next, the unprocessed ceramic body is fired. In this firing step, the green ceramic sheets become the ceramic layers 3. Thereafter, a step of forming the external electrodes 6 and 7 on the end faces of the ceramic body 2 is performed.

[0034] It is characterized in that the conductive material for forming the external electrodes 6 and 7 contains nano-CuO particles that become metallic copper as a conductive component through firing, a glass raw material mixture that becomes glass through firing, and a solvent that dissolves or disperses the nano-CuO particles and the glass raw material mixture. The glass raw material mixture contains a metal salt in a powder state having a particle size of 100 nm or less and becoming a melting point or higher during firing, or a metal salt in an ionic form.

[0035] Such a conductive material is initially in a sol state and is provided to the surface of the ceramic body 2, more specifically, to the opposing end faces. Next, after becoming a gel state through heat drying, it is fired at a temperature above the melting point of the metal salt contained in the glass raw material mixture, and the glass raw material mixture is vitrified while flowing.

[0036] In Figure 2 Shown in Figure 1 A part of the first external electrode 6 of the multilayer ceramic capacitor 1 is enlarged and schematically shown in a cross-sectional view. Although not shown in Figure 2 The second external electrode 7 has substantially the same structure as the first external electrode 6.

[0037] In addition, Figures 3 to 5 Is a SEM image of the cross-section of the conductor film 12 formed on the substrate 11 in the experimental example described later. However, since the structure of the conductor film 12 is also adopted in the external electrodes 6 and 7, in the following description, these Figures 3 to 5 May be referred to. In addition, Figure 4 Shown in Figure 3 A SEM image of a further enlarged part of the conductor film 12 is shown, Figure 5 Is in Figure 4 The SEM image shown is a diagram with a circle EC surrounding the glass domain 13 drawn in.

[0038] As a result of the above-mentioned firing, regarding the first external electrode 6 as shown in Figure 2 A glass layer 14 is formed along the interface where the external electrodes 6 and 7 and the ceramic layer 3 of the ceramic body 2 are in contact. In Figures 3 to 5 The part extending along the interface where the substrate 11 and the conductor film 12 are in contact is the glass layer 14. In Figures 3 to 5 In, the glass layer 14 appears as a blackened part.

[0039] Referring to Figure 2 , the glass layer 14 achieves a firm bonding state between the copper contained in the external electrodes 6 and 7 and the ceramic body 2. As described above, since the firing temperature is set above the melting point of the metal salt contained in the glass raw material mixture, the wetting and densification of the glass contained in the external electrodes 6 and 7 toward the base surface 15 can be promoted.

[0040] In Figures 3 to 5 the SEM image of , multiple glass domains 13 represented by darker regions are captured in the conductor film 12. When observing a cross-section of the conductor film 12 along the thickness direction, these glass domains 13 are not in contact with either the surface 16 or the base surface 15 of the conductor film 12, and are surrounded by copper 17. The glass domains 13 do not mix with copper 17 and are distributed in small sizes.

[0041] If, with reference to Figure 2 , the conductor film 12 is replaced with the external electrodes 6 and 7 to illustrate the above structure, in the external electrodes 6 and 7, when observing a cross-section along their thickness direction, there are multiple glass domains including glass that are not in contact with either the surface 16 or the base surface 15 in this cross-section and are surrounded by copper. These glass domains do not mix with copper and are distributed in small sizes.

[0042] To more clearly define this situation, as Figure 5 shown, the concept of a circle EC that encloses the glass domain 13 is introduced and numerically defined as follows. That is, the average of the diameters of the enclosing circle EC is 0.5 μm or more and 0.7 μm or less, the standard deviation of the diameters of the enclosing circle EC is 0.3 μm or more and 0.5 μm or less, and the ratio of the maximum diameter of the enclosing circle EC to the thickness direction dimension of the external electrodes 6 and 7 is less than 1.

[0043] Regarding the first external electrode 6, as Figure 2 shown, in the external electrodes 6 and 7, a plating film 8 is formed as needed. Although the plating film 8 is not shown in detail, for example, it is composed of a Cu plating layer, an Ni plating layer thereon, and an Sn plating layer thereon.

[0044] In this way, even if the firing of the conductive materials that become the external electrodes 6 and 7 is advanced until the copper part and the ceramic body 2 are joined through the glass layer 14, the size of the glass domain 13 can be maintained in a small and uniform state. Therefore, it is not easy to generate glass domains that penetrate from the surface 16 to the base surface 15 of the external electrodes 6 and 7. Thus, the intrusion of moisture from the glass part on the surface of the external electrodes 6 and 7 can be suppressed. In addition, the significant exposure of glass on the surface of the external electrodes 6 and 7 is also suppressed, and good plating adhesion can be ensured.

[0045] It is presumably because the external electrodes 6 and 7 having the above-described advantages are obtained by using the conductive material according to the present invention and firing the conductive material according to the manufacturing method according to the present invention. The reason is that since the conductive material contains nano-CuO particles as a conductive component and contains a metal salt in a powder state having a particle size of 100 nm or less or a metal salt in an ionic form as a glass raw material mixture, even when firing is performed at a temperature above the melting point of the glass raw material mixture to cause fusion of the glasses, the glass domains can maintain a small and uniform state.

[0046] The conductive material according to the present invention is also characterized in that a thin conductor film can be formed. For example, as can be seen from the experimental examples described later, the thickness direction dimension of the external electrodes 6 and 7 can be set to be 2.4 μm or more and 4.6 μm or less.

[0047] The aforementioned metal salt contained in the glass raw material mixture contained in the conductive material for forming the external electrodes 6 and 7 contains, for example, any one of metal carboxylates and metal nitrates.

[0048] In addition, the glass contained in the external electrodes 6 and 7 contains, for example, SiO 2 and B 2 O 3 , and contains at least one oxide of an alkali metal and an alkaline earth metal.

[0049] The weight ratio of the content of the glass raw material mixture contained in the conductive material for forming the external electrodes 6 and 7 to the content of the nano-CuO particles as a conductive component, in terms of the weight after metal-copper conversion of the nano-CuO particles and the weight after vitrification of the glass raw material mixture, is preferably 0.13 or more and 0.57 or less.

[0050] For viscosity adjustment and the like, the conductive material for forming the external electrodes 6 and 7 may contain an organic binder. As the organic binder, for example, hydroxypropyl cellulose can be advantageously used.

[0051] The present invention has been described above in relation to the external electrodes of the multilayer ceramic capacitor, but as long as it is a ceramic electronic component having a ceramic body and a conductor film provided on the surface of the ceramic body, the present invention can also be applied to ceramic electronic components other than the multilayer ceramic capacitor.

[0052] Next, experimental examples carried out to confirm the effects based on the present invention will be described.

[0053] [Examples]

[0054] [Production of Conductive Material]

[0055] A sol-state conductive material containing the following (1) to (7) was produced.

[0056] (1) 50-nm diameter nano-silica surface-treated with silane methacrylate (“ADMANANO” manufactured by Admatechs): 1.5 mass%,

[0057] (2) Boric acid: 0.92 mass%,

[0058] (3) Lithium nitrate (melting point: 260 °C): 0.48 mass%,

[0059] (4) Sodium nitrate (melting point: 306 °C): 0.66 mass%,

[0060] (5) 50-nm diameter nano-CuO particles: 27.60 mass%,

[0061] (6) Hydroxypropyl cellulose (2.0 to 2.9 @ 20 °C / 2% aqueous solution): 11.60 mass%,

[0062] (7) Diethylene glycol monoethyl ether: 43.80 mass%.

[0063] The above (1) to (4) are glass raw materials that become glass through firing. (5) are nano-CuO particles that become metallic copper as a conductive component through firing. (6) is an organic binder. (7) is a solvent.

[0064] <Coating / Firing>

[0065] After coating the above conductive material on a barium titanate substrate using a doctor blade with a 50-μm gap, it was dried at 150 °C for 30 minutes to make the conductive material gel-like. Then, the gel-like conductive material was fired in an N 2 atmosphere at a temperature of 780 °C, which is above the melting points of the above (3) and (4), to obtain a conductor film specimen.

[0066] <Conductor Film Structure Analysis>

[0067] After resin embedding and polishing the conductor film specimen and extracting the cross-section, FE-SEM (manufactured by JEOL Ltd.: JSM-6335F) observation was carried out under the following conditions.

[0068] · Pretreatment before observation: Au+Pd sputtering,

[0069] · Magnification: ×2000,

[0070] · Acceleration voltage: 5 kV,

[0071] · WD: 15 to 18 mm.

[0072] Figure 3 This is a SEM image of the cross-section of a specimen of the conductor film 12 involved in the example. Figure 4 This is Figure 3 a further magnified SEM image of a part of the conductor film 12 shown.

[0073] In Figure 3 and Figure 4 the blackened part extending along the substrate 11 in the conductor film 12 is the glass layer 14. As can be seen from Figure 3 it is confirmed that the glass layer 14 is formed in a wetting and spreading manner between the conductor film 12 and the substrate 11 over more than half of the width direction of the obtained image.

[0074] Next, using image analysis software (manufactured by Mitani Corporation: WinROOF2021), based on the obtained image, the film thickness of the conductor film 12 was measured, and as Figure 5 shown, taking the glass domains 13 that are not in contact with the surface 16 and the bottom surface 15 in the cross-section of the conductor film 12 as the fired film and are surrounded by copper 17 as the objects, circles EC surrounding them were respectively drawn. For the drawn surrounding circles EC, the maximum diameter, average diameter, and standard deviation were obtained, and the maximum diameter / film thickness was calculated. These operations were performed for a total of 6 fields of view per field of view. The results are shown in Table 1.

[0075] [Table 1]

[0076] Table 1

[0077]

[0078] [Comparative Example]

[0079] [Fabrication of Conductive Material]

[0080] A conductive material with the following composition was fabricated using a roll mill.

[0081] · Cu powder (average particle size 4 μm, flaky): 100 parts by mass,

[0082] · Glass powder (average particle size 3.3 μm): 10 parts by mass,

[0083] · Carrier obtained by dissolving an acrylic resin-based binder in terpineol: 40 parts by mass.

[0084] [Coating / Firing]

[0085] After coating the above conductive material in the same manner as in the example, firing was performed at a temperature of 860 °C in an N 2 atmosphere with an oxygen concentration of 5 ppm to obtain a conductor film specimen.

[0086] <Conductive film structure analysis>

[0087] The structure analysis of the conductive film specimen was carried out in the same manner as in the case of the embodiment.

[0088] Figure 6 It is an SEM image of the cross-section of the specimen of the conductive film 22 related to the comparative example.

[0089] In Figure 6 the blackened part extending along the substrate 21 in the conductive film 22 is the glass layer 23. It can be seen from Figure 6 that it was confirmed that the glass layer 23 was formed by wetting and spreading between the conductive film 22 and the substrate 21 over more than half of the width direction of the obtained image.

[0090] In the same manner as in the case of the embodiment, the maximum diameter, average diameter, and standard deviation of the circumscribed circle of the glass domain 24 were obtained, and further the film thickness was obtained, and the maximum diameter / film thickness was calculated. The results are shown in Table 2.

[0091] [Table 2]

[0092] Table 2

[0093]

[0094] [Discussion]

[0095] In Table 3 below, the distribution ranges of the values of the maximum diameter, average diameter, standard deviation, film thickness, and maximum diameter / film thickness of the circumscribed circle EC of the glass domain 13 in the embodiment shown in Table 1 and the distribution ranges of the values of the maximum diameter, average diameter, standard deviation, film thickness, and maximum diameter / film thickness of the circumscribed circle of the glass domain 24 in the comparative example shown in Table 2 are shown in comparison. In addition, in Table 3, each value is rounded to one decimal place.

[0096] [Table 3]

[0097] Table 3

[0098]

[0099] In Table 3, first, when comparing the film thickness, it can be seen that in the embodiment, it is 2.4 μm or more and 4.6 μm or less, and in the comparative example, it is 12.5 μm or more and 20.3 μm or less. The embodiment can overwhelmingly reduce the film thickness compared to the comparative example. This can also be confirmed for Figure 3 and Figure 6 shown on the same scale.

[0100] In addition, as shown in Table 3, it was confirmed that in the examples, particularly with an average diameter of 0.5 to 0.7 μm and a standard deviation of 0.3 to 0.5 μm, the size of the glass region 13 was small and uniform compared to the average diameter of 1.9 to 3.0 μm and the standard deviation of 1.3 to 3.8 μm in the comparative examples.

[0101] In addition, in the examples, since the maximum diameter / thickness of the film was 0.3 to 0.6 and thus less than 1, it was possible to judge that the state in which the glass region penetrated from the surface 16 of the conductor film 12 to the base surface 15 was not likely to be generated.

[0102] In the comparative examples, the average diameter of the circle surrounding the glass region became 1.9 to 3.0 μm and the standard deviation became 1.3 to 3.8 μm. Comparing with the results of the examples, it was confirmed that the glass region was large and non-uniform.

[0103] In addition, in the comparative examples, since there was one or more fields of view with a maximum diameter / thickness of 0.3 to 1.1, it was possible to judge that the possibility of generating a glass region penetrating from the surface of the conductor film 22 to the base surface was high.

[0104] Based on the above, it can be speculated that in the comparative examples, the CuO particles and glass raw material particles in the conductive material were large. When firing was advanced until the state where Cu and the substrate 21 were joined was achieved, fusion of the glasses occurred and the glass region became larger. Thus, it can be speculated that a glass region penetrating from the surface of the conductor film 22 to the base surface might be formed, and immersion of the plating solution into the conductor film 22 might occur. In addition, it can be speculated that on the surface of the conductor film 22, the glass region also became larger, and poor plating adhesion might occur.

[0105] On the contrary, in the examples, since Cu in the conductive material was made into nano-CuO particles and the glass raw material mixture contained a metal salt in a powder state with a particle size of 100 nm or less or was made into an ionic metal salt, when fusion of the glasses occurred, the glass region 13 could also maintain a small and uniform state. Thus, formation of a glass region penetrating from the surface 16 of the conductor film 12 to the base surface 15 could be suppressed, and immersion of the plating solution into the conductor film 12 could be suppressed. In addition, significant exposure of the glass on the surface 16 of the conductor film 12 was suppressed, and good plating adhesion could be obtained.

[0106] In the embodiment of the present invention, there is the following mode.

[0107] <1>

[0108] A conductive material for forming a conductor film provided on the surface of a ceramic body by firing, wherein,

[0109] The conductive material includes: nano-CuO particles that become metallic copper as a conductive component through firing, a glass raw material mixture that becomes glass through firing, and a solvent that dissolves or disperses the nano-CuO particles and the glass raw material mixture.

[0110] The glass raw material mixture includes a metal salt in a powder state with a particle size of 100 nm or less or a metal salt in an ionic form.

[0111] <2>

[0112] In the conductive material described in <1>, the metal salt includes any one of metal carboxylate and metal nitrate.

[0113] <3>

[0114] In the conductive material described in <1> or <2>, the conductive material is used to form an external electrode of a multilayer ceramic capacitor.

[0115] <4>

[0116] In the conductive material described in any one of <1> to <3>, the weight ratio of the content of the glass raw material mixture to the content of the nano-CuO particles, converted to the weight after the metal copper conversion of the nano-CuO particles and the weight after the vitrification of the glass raw material mixture, is 0.13 or more and 0.57 or less.

[0117] <5>

[0118] In the conductive material described in any one of <1> to <4>, the solvent includes diethylene glycol monoethyl ether.

[0119] <6>

[0120] In the conductive material described in any one of <1> to <5>, the conductive material further includes an organic binder.

[0121] <7>

[0122] In the conductive material described in <6>, the organic binder includes hydroxypropyl cellulose.

[0123] <8>

[0124] A method for manufacturing a ceramic electronic component

[0125] The ceramic electronic component includes a ceramic body and a conductor film provided on the surface of the ceramic body.

[0126] Among them, the method for manufacturing the ceramic electronic component includes:

[0127] The step of providing the conductive material described in any one of <1> to <7> to the surface of the ceramic body in order to form the conductor film;

[0128] Next, the step of heating and drying the glass raw material mixture contained in the conductive material; and

[0129] Next, the step of firing at a temperature above the melting point of the glass raw material mixture to form the conductor film.

[0130] <9>

[0131] A ceramic electronic component, comprising:

[0132] A ceramic body; and

[0133] A conductor film provided on the surface of the ceramic body,

[0134] The conductor film contains copper and glass,

[0135] When observing a cross-section of the conductor film along the thickness direction, there are a plurality of glass domains including the glass that are not in contact with either the surface or the base surface in the cross-section and are surrounded by the copper. The average of the diameters of the circles surrounding the glass domains is 0.5 μm or more and 0.7 μm or less, the standard deviation of the diameters of the circles is 0.3 μm or more and 0.5 μm or less, and the ratio of the maximum diameter of the circle to the thickness direction dimension of the conductor film is less than 1.

[0136] <10>

[0137] In the ceramic electronic component described in <9>, the thickness direction dimension of the conductor film is 2.4 μm or more and 4.6 μm or less.

[0138] <11>

[0139] In the ceramic electronic component described in <9> or <10>, the glass contains SiO 2 and B 2 O 3 and contains at least one oxide of an alkali metal and an alkaline earth metal.

[0140] <12>

[0141] In the ceramic electronic component described in any one of <9> to <11>, the ceramic electronic component further includes a plating film formed on the conductor film.

[0142] <13>

[0143] In the ceramic electronic component according to any one of <9> to <12>, the ceramic body includes: a plurality of stacked ceramic layers, and a plurality of internal electrodes respectively disposed along a plurality of interfaces between the ceramic layers.

[0144] The conductor film provides a plurality of external electrodes provided on the surface of the ceramic body and electrically connected to the internal electrodes.

[0145] The ceramic electronic component constitutes a multilayer ceramic capacitor.

[0146] Description of Reference Numerals

[0147] 1 Multilayer ceramic capacitor

[0148] 2 Ceramic body

[0149] 3 Ceramic layer

[0150] 4, 5 Internal electrodes

[0151] 6, 7 External electrodes

[0152] 8 Plated film

[0153] 11 Substrate

[0154] 12 Conductor film

[0155] 13 Glass region

[0156] 14 Glass layer

[0157] 15 Base surface

[0158] 16 Surface

[0159] 17 Copper

[0160] EC enclosing circle.

Claims

1. A conductive material for forming a conductor film provided on the surface of a ceramic body by firing. Among them, the conductive material includes: nano-CuO particles that become metallic copper as a conductive component by firing, a glass raw material mixture that becomes glass by firing, and a solvent that dissolves or disperses the nano-CuO particles and the glass raw material mixture. The glass raw material mixture includes metal salts in powder form with a particle size of 100 nm or less or metal salts in ionic form.

2. The conductive material according to claim 1, Among them, the metal salt includes any one of metal carboxylates and metal nitrates.

3. The conductive material according to claim 1 or 2, Among them, the conductive material is used to form an external electrode of a multilayer ceramic capacitor.

4. The conductive material according to any one of claims 1 to 3, Among them, the weight ratio of the content of the glass raw material mixture to the content of the nano-CuO particles, converted to the weight after the metal copper conversion of the nano-CuO particles and the weight after the vitrification of the glass raw material mixture, is 0.13 or more and 0.57 or less.

5. The conductive material according to any one of claims 1 to 4, Among them, the solvent includes diethylene glycol monoethyl ether.

6. The conductive material according to any one of claims 1 to 5, Among them, the conductive material further includes an organic binder.

7. The conductive material according to claim 6, Among them, the organic binder includes hydroxypropyl cellulose.

8. A method for manufacturing a ceramic electronic component, the ceramic electronic component includes a ceramic body and a conductor film provided on the surface of the ceramic body, Among them, the method for manufacturing the ceramic electronic component includes: a step of providing the conductive material according to any one of claims 1 to 7 on the surface of the ceramic body in order to form the conductor film; next, a step of heating and drying the glass raw material mixture included in the conductive material; and next, a step of firing at a temperature equal to or higher than the melting point of the glass raw material mixture to form the conductor film.

9. A ceramic electronic component, comprising: a ceramic body; and a conductor film provided on the surface of the ceramic body, the conductor film includes copper and glass, when observing a cross-section of the conductor film along the thickness direction, there are a plurality of glass domains including the glass that are not in contact with either the surface or the bottom surface in the cross-section and are surrounded by the copper. The average diameter of the circles surrounding the glass domains is 0.5 μm or more and 0.7 μm or less, the standard deviation of the diameter of the circles is 0.3 μm or more and 0.5 μm or less, and the ratio of the maximum diameter of the circles to the thickness direction dimension of the conductor film is less than 1.

10. The ceramic electronic component according to claim 9, Among them, the thickness direction dimension of the conductor film is 2.4 μm or more and 4.6 μm or less.

11. The ceramic electronic component according to claim 9 or 10, Among them, The glass contains SiO 2 and B 2 O 3 , and contains an oxide of at least one of an alkali metal and an alkaline earth metal.

12. The ceramic electronic component according to any one of claims 9 to 11, Among them, The ceramic electronic component further includes a plating film formed on the conductor film.

13. The ceramic electronic component according to any one of claims 9 to 12, wherein the ceramic body includes: a plurality of stacked ceramic layers, and a plurality of internal electrodes respectively disposed along a plurality of interfaces between the ceramic layers, the conductor film is a plurality of external electrodes provided on the surface of the ceramic body and electrically connected to the internal electrodes, the ceramic electronic component constitutes a multilayer ceramic capacitor.

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