JP7046679B2 - External electrodes of ceramic laminate - Google Patents

Description

The present invention relates to an external electrode provided on a ceramic laminate.

In addition to quality advantages such as temperature stability and moisture resistance, monolithic ceramic products are suitable for use in high frequency bands, so demand for laminated ceramic products has increased dramatically in recent years as board mounting components. In particular, demand for multilayer ceramic capacitors (MLCCs) and multilayer inductors (MLCIs) for smartphones and in-vehicle sensors is strong.

The MLCC is mounted on a substrate and plays a role of temporary storage and noise reduction. As the frequency at which electronic devices are used shifts to higher frequency bands, higher performance is desired. The MLCC is usually manufactured by the following procedure. Nickel powder paste is printed on a green sheet composed of ceramic particles containing BaTiO ₃ as a main component, laminated, and fired at around 1000 ° C. A copper powder paste that is cut to a desired size and forms an external electrode is applied and baked at around 800 ° C. In order to mount the obtained MLCC on the substrate, nickel plating is performed on the external electrode, and then tin plating is performed. The nickel-plated layer protects the external electrode obtained by firing from so-called solder erosion. The tin layer is provided as a bonding layer for mounting with solder.

MLCI is used for matching in the RF section, resonance circuit, etc. in a high frequency substrate such as a mobile phone or a wireless LAN. After forming via holes in a green sheet composed of ferrite particles, ceramic particles, etc., a silver powder paste is printed. This sheet is laminated and fired at around 900 ° C., then cut to a desired size, coated with a copper powder paste forming an external electrode, and baked at around 800 ° C. In order to mount the obtained MLCI on the substrate, nickel plating and tin plating are performed on the external electrodes in the same manner as in MLCC.

Both MLCC and MLCI are desired to be reduced in size while maintaining the performance in the conventional size.

The size of laminated ceramic products is standardized by JIS. For example, the MLCC is designed to have the same height and width, so the '1005' has a length of 1.0 mm and a width of 0.5 mm, and the '0603' has a length of 0.6 mm and a width of 0.3 mm. Represents. Under these restrictions, efforts have been made to reduce the thickness of each layer of the laminated ceramic product and increase the number of layers so that the electrical characteristics are not impaired even if the size of the laminated ceramic product is reduced. There is. In this way, efforts are being made to improve the electrical characteristics while maintaining the size.

As a general external electrode paste, as described in Patent Document 1 (Japanese Patent Laid-Open No. 2002-277372), a paste composed of a binder resin and a solvent in a copper powder having a size of about 1 μm is widely used. .. In this paste material, if the inorganic component is only Cu powder, voids are generated in the fired body and cause peeling from the ceramic prime field, so glass frit is added. Since the glass frit fills the voids, the adhesion between the ceramic prime field and the external electrode obtained by firing is ensured.

Patent Document 2 (Japanese Patent Laid-Open No. 2011-18898) discloses the manufacture of a monolithic ceramic capacitor with improved yield, and nickel paste is used for the internal electrode.

Patent Document 3 (WO2013 / 118893A1) and Patent Document 4 (WO2013 / 125659) disclose a surface-treated metal powder suitable for a paste for an internal electrode and a method for producing the same.

Japanese Unexamined Patent Publication No. 2002-277372 Japanese Unexamined Patent Publication No. 2011-18898 WO2013 / 118893 WO2013 / 125659

As described above, it is required to reduce the size of laminated ceramic products such as MLCC while maintaining the performance, or to improve the performance while maintaining the size. On the other hand, the present inventor increases the area per layer of the laminated ceramic product by thinning the external electrode formed on the laminated ceramic product, and as a result, increases the total internal electrode area. , I got the idea of achieving high performance with the same size.

Therefore, an object of the present invention is to provide a thinned external electrode for a laminated ceramic product, particularly an external electrode of MLCC, while maintaining the adhesion to the laminate required for the external electrode. ..

As a result of diligent research, the present inventor has made a thin layer without forming a conventional Cu electrode as an external electrode in a laminate by using a Ni powder paste having excellent sintering delay as an external electrode material. The present invention was reached by finding that an external electrode can be manufactured.

Therefore, the present invention includes the following (1).
(1)
An external electrode provided on a ceramic laminate,
It consists of a Ni layer provided on the laminated end face of the ceramic laminate and a Sn plating layer provided on the Ni layer.
The Ni layer has a thickness of 1 to 20 μm and has a thickness of 1 to 20 μm.
An external electrode having a Si content of 0.05 to 3.0% by mass with respect to the Ni content in the Ni layer.

According to the present invention, the external electrode of the laminated ceramic product can be thinned.

Hereinafter, the present invention will be described in detail with reference to embodiments. The present invention is not limited to the specific embodiments listed below.

[External electrode]
The external electrode of the present invention is an external electrode provided on the ceramic laminate, and is composed of a Ni layer provided on the laminated end face of the ceramic laminate and a Sn plating layer provided on the Ni layer, and the Ni layer is formed. The thickness is 1 to 20 μm, and the Si content in the Ni layer can be 0.05 to 3.0% by mass with respect to the Ni content.

[Ceramic laminate and external electrodes]
The ceramic laminate is a part that becomes the main body of a ceramic laminate product, for example, a multilayer ceramic capacitor (MLCC) or a multilayer inductor (MLCI). For example, in a laminated ceramic capacitor, a ceramic layer and an internal electrode layer are alternately laminated in a ceramic laminate, and on two facing surfaces of the ceramic laminate, the laminated internal electrodes are alternately exposed and face each other. External electrodes are provided on the two surfaces (laminated end faces) so that the internal electrodes exposed on each surface are electrically connected to each other and at the same time can be electrically connected to the outside, as a laminated ceramic capacitor. used. The laminated end surface is a surface of the ceramic laminate in which the laminated internal electrodes are alternately exposed, and external electrodes are installed therein. As the area of the internal electrode surface is large, for example, the capacity of the capacitor is increased, which is preferable. Therefore, the area of the internal electrode surface has been increased by increasing the number of laminated layers. The present inventor came up with the idea of increasing the area of the internal electrode surface even with the same number of layers by thinning the external electrode, and by using the external electrode having the above configuration, the share strength was maintained. The present invention was reached by finding that the layer can be thinned as it is.

[Ceramic layer]
In a preferred embodiment, the ceramic layer used in the ceramic laminate can be a commonly used ceramic layer, eg, BaTIO ₃ (barium titanate), CaZrO ₃ (calcium titanate), CaTIO. ₃ (calcium titanate), SrTiO ₃ (strontium titanate), Ba _{1-xy CaxSry} Ti _1-z Zr _z O ₃ (0 ≦ x ≦ 1,0 ≦ y ≦ 1,0 ≦ z) forming a perovskite structure ≦ 1), ferrite containing NiCuZn as a main component, a mixture of glass (CaO, SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ ) and alumina, and the like can be mentioned.

[Internal electrode layer]
In a preferred embodiment, the internal electrode layer used in the ceramic laminate can be an internal electrode layer made of a commonly used metal, such as Ni (nickel), Cu (copper), Sn (tin). Examples thereof include metals containing the above as a main component, precious metals such as Pt (platinum), Pd (platinum), Ag (silver), and Au (gold), and alloys containing these.

[Ni layer and thickness]
The Ni layer of the present invention is provided directly on the laminated end face of the ceramic laminate, whereby the internal electrode layers exposed on the laminated end face are electrically connected to each other. Further, the Ni layer of the present invention realizes sufficient strength of adhesion to the internal electrode layer exposed on the laminated end face and the ceramic layer, and achieves the durability of the laminated ceramic product.

In the conventional technique, it is usual that a Cu layer is once provided on the laminated end face of the ceramic laminate. The internal electrode layers exposed from the Cu layer were electrically connected to each other to achieve sufficient strength of adhesion to the laminated end face, thereby forming a laminated ceramic product. The electrical connection by installing the Cu layer is sufficiently good, and the adhesion to the laminated end face is also good, but the structure requires a thickness of, for example, 30 to 100 μm.

In a preferred embodiment, the Ni layer of the present invention has a thickness of, for example, 1 to 20 μm, preferably 1 to 15 μm, more preferably 1 to 11 μm, or 1 to 10 μm, 1 to 8 μm, 1 to 6 μm. It can be in the range of 1 to 5 μm, 1 to 4 μm, 1 to 3 μm, and 1 to 2 μm. By providing the Ni layer thinned in this way on the laminated end face to realize electrical connection and adhesion, it is possible to achieve a wider internal electrode area than when the Cu layer is adopted.

[Si content in Ni layer]
In a preferred embodiment, the Ni layer of the present invention has a Si content of, for example, 0.05 to 3.0% by mass, preferably 0.05 to 2.0% by mass, based on the Ni content in the Ni layer. More preferably, it can be in the range of 0.05 to 1.5% by mass.

[Sn plating layer]
In a preferred embodiment, the Sn plating layer provided on the Ni layer can have a thickness in the range of, for example, 0.5 to 10 μm, preferably 0.5 to 5 μm, and more preferably 1 to 5 μm. .. The Sn plating layer can be formed by a known means, for example, electroless Sn plating or electrolytic Sn plating.

In the conventional technique, when a Cu layer is used for adhesion to the laminated end face and electrical connection, a Ni layer is once provided on the Cu layer by plating or the like, and a Sn plating layer is provided on the Cu layer. However, in the present invention, since the Ni layer is used for adhesion and electrical connection with the laminated end face, it is not necessary to install another layer on the Ni layer, and a Sn plating layer is provided. It is advantageous to be able to. According to the present invention, since the Ni plating step for forming the Ni layer, which is required in the conventional technique, can be omitted, it is advantageous in terms of improving the productivity associated therewith.

[Fired Ni layer]
In a preferred embodiment, the Ni layer of the present invention can be a fired Ni layer formed by firing a Ni paste.

In a preferred embodiment, the fired Ni layer is formed by immersing a Ni paste described later in a laminated end face of a ceramic laminate, burning a binder resin at, for example, 400 to 600 ° C, and then reducing the atmosphere at 600 to 1000 ° C. Alternatively, it can be prepared by firing in a steam atmosphere. Alternatively, for example, Ni paste may be applied to the laminated end face by dipping or spraying.

[Ni paste]
In a preferred embodiment, the Ni paste is prepared using surface treated Ni powder. The Ni paste can be prepared, for example, by kneading the surface-treated Ni powder with a binder resin, an organic solvent, and a glass frit, and if desired, a dispersant, a thixo agent, and / or an antifoaming agent may be added. good.

Examples of the binder resin include ethyl cellulose, acrylic resin and butyral resin. The binder resin in the Ni paste can be contained in a ratio of, for example, 0.1 to 10% with respect to the mass of the Ni powder. Examples of the organic solvent include tarpineol, butyl carbitol and hexane. As the glass frit, for example, a glass frit having a diameter in the range of 0.1 to 10 μm, preferably 0.1 to 5.0 μm can be used. Examples of the dispersant include oleic acid, stearic acid and oleylamine. Examples of the defoaming agent include organically modified polysiloxane and polyacrylate. In the Ni paste, the mass ratio of the Ni powder to the mass of the Ni paste is 30 to 90%, the mass ratio of the glass frit is 0 to 5%, the mass ratio of the binder resin is as described above, and the balance. Can be contained as an organic solvent, a dispersant, or the like. Kneading can be performed using known means. The Ni paste from the surface-treated Ni powder can be prepared, for example, according to the preparation of the paste disclosed in Patent Document 4 (WO2013 / 125659).

[Surface-treated Ni powder]
In a preferred embodiment, the Ni powder used in the Ni paste is a surface-treated Ni powder. In a preferred embodiment, as the surface-treated Ni powder, for example, Ni powder having a BET specific surface area of 0.8 m ² g ^-1 or more and a sintering start temperature of 600 ° C. or more can be used.

In a preferred embodiment, the surface-treated Ni powder can be prepared by treating the Ni powder with a coupling agent. As the coupling agent, for example, a known coupling agent having an amino group at the terminal can be used, and for example, the coupling agent disclosed in Patent Document 3 (WO2013 / 118893A1) is the procedure disclosed in the same document. Can be used in. For example, the Ni powder surface-treated as a cake can be recovered after the Ni powder is put into an aqueous solution of the coupling agent and stirred.

[Share strength]
In the external electrode of the present invention, the Ni layer is directly provided on the laminated end face of the ceramic laminate without providing the Cu layer to reduce the thickness and at the same time, the external electrode is bonded to the ceramic laminate with sufficient strength. .. The strength of the external electrode bonded to the ceramic laminate can be expressed by the shear strength. The share strength can be measured by known means. The shear strength can be used as an index showing durability by measuring the shear strength after a predetermined cycle test. In the present invention, the cycle test is a test in which one cycle (1 time) from −55 ° C. (15 minutes) to returning to −55 ° C. via 125 ° C. (15 minutes) is regarded as one cycle (1 time), and the temperature is changed to 0. The share strengths of the first time (before the cycle test) and after 1000 cycles (after 1000 times) are compared. In a preferred embodiment, the share strength is, for example, 290 to 1000 [gf], preferably 290, in 0 cycle tests for a laminated ceramic product having a length of 0.4 mm, a width and a height of 0.2 mm. It can be set to ~ 500 [gf], and after 1000 cycles of the cycle test, it can be set to, for example, 100 to 500 [gf], preferably 200 to 500 [gf]. Since the shear strength, which represents the adhesion of the laminated ceramic product to the substrate, varies depending on the ground contact area, that is, the size of the laminated ceramic product, it is preferable to look at the deterioration rate of the shear strength as an index of durability. In a preferred embodiment, the share strength after 1000 cycle tests is, for example, 0.5 or more, preferably 0.73 or more, and more preferably 0.81 or more with respect to the share strength at the 0th cycle test. It can be a ratio value.

[Thickness of external electrode]
In a preferred embodiment, the external electrode of the present invention can have a thickness including the Ni layer and the Sn plating layer, for example, 1.5 to 30 μm, preferably 3 to 20 μm, and more preferably 3 to 5 μm. ..

[Preferable embodiment]
The present invention includes the following (1) embodiments.
(1)
An external electrode provided on a ceramic laminate,
It consists of a Ni layer provided on the laminated end face of the ceramic laminate and a Sn plating layer provided on the Ni layer.
The Ni layer has a thickness of 1 to 20 μm and has a thickness of 1 to 20 μm.
An external electrode having a Si content of 0.05 to 3.0% by mass with respect to the Ni content in the Ni layer.
(2)
The external electrode according to (1), wherein the Sn plating layer has a thickness of 0.5 to 10 μm.
(3)
The external electrode according to any one of (1) to (2)), wherein the Ni layer is a fired Ni layer formed by firing Ni paste.
(4)
The external electrode according to any one of (1) to (3), wherein the ceramic laminate is a ceramic laminate in which an internal electrode layer and a ceramic layer are laminated.
(5)
A laminated ceramic product in which the external electrode according to any one of (1) to (4) is provided on the laminated end face of the ceramic laminate.
(6)
The ceramic laminate is a rectangular parallelepiped shape,
A laminated ceramic product in which the external electrodes according to any one of (1) to (5) are provided on two facing surfaces of the laminated end faces of the ceramic laminate.
(7)
The laminated ceramic product according to (6), wherein the laminated ceramic product is a laminated ceramic capacitor or a laminated ceramic inductor.

Therefore, the present invention includes an external electrode provided on the ceramic laminate, a laminated ceramic product in which the external electrode is provided on the ceramic laminate, and includes a laminated ceramic capacitor and a laminated ceramic inductor.

Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to the following examples.

(Example 1: Fabrication of laminated portion)
A laminated portion of MLCC was prepared by the method described in JP-A-2011-18898. That is, 30% by weight of Ni powder having a BET specific surface area of 3.4 m ² g ^-1 , 6% by weight of sulfur-containing high crystalline barium titanate having an average particle diameter of 100 nm, 7.0% by weight of ethyl cellulose, and 0% by weight of oleic acid. A Ni powder paste for an internal electrode consisting of 5% by weight and 56.5% of tarpineol was dispersed in three rolls with a roll gap of 5 μm. This Ni powder paste was printed on a barium titanate ceramic sheet (thickness 4 μm) on an electrode pattern, and 20 layers were laminated. This was oxidized in N ₂ containing 3% of H ₂ at 1230 ° C. for 2 hours, and further in N ₂ at 1000 ° C. for 3 hours.

(Example 2: Preparation of Ni powder paste for external electrode 1) (Example 1)
2 kg of Toho Titanium Ni powder NF32 (3.2 m ² g ^-1 ) was surface-treated with 2.5 L of an 8% diaminosilane aqueous solution (A-1120) according to the procedure of Example 1 of WO2013 / 1118893. The cake was collected by solid-liquid separation. This was dried in an N ₂ atmosphere at 100 ° C. for 2 hours, coarsely crushed with a pestle and a mortar until it passed through a 1 mm sieve, and crushed with a jet mill. This powder was molded to a green compact density of 4.9 gcm ^-3 and subjected to TMA (2% H ₂ , 5 ° C./min, 10 mN). The temperature at the time of 1% volume shrinkage was 910 ° C.
This Ni powder is Ni: ethyl cellulose: oleic acid: tarpineol = 73: 2.2: 1.6: 23.2
The roll gap was set to 5 μm, and 5 passes were passed through 3 rolls to obtain a Ni powder paste for an external electrode.

(Example 3: Preparation of Ni powder paste for external electrode 2) (Example 2)
The surface-treated Ni powder prepared in Example 2 was prepared with the following composition and passed through three rolls under the same conditions to obtain a Ni powder paste for an external electrode.
Ni: Ethyl cellulose: Oleic acid: Tarpineol = 71: 2.1: 1.6: 25.3

(Example 4: Preparation of Ni powder paste for external electrode 3) (Example 3)
The surface-treated Ni powder prepared in Example 2 was prepared with the following composition and passed through three rolls under the same conditions to obtain a Ni powder paste for an external electrode.
Ni: Ethyl cellulose: Oleic acid: Tarpineol = 75: 2.3: 1.6: 21.1

(Example 5: Preparation of Ni powder paste for external electrode 5) (Example 4)
Using the Ni powder before surface treatment used in Example 2 and a glass frit (Ad Rate Co., Ltd., D672) having an average particle size of 3 μm, a paste having the following composition was prepared.
Ni: Ethyl cellulose: Oleic acid: Tarpineol: Glass frit = 73: 2.2: 1.6: 22.2: 1.0

(Example 6: Preparation of Ni powder paste for external electrode 6) (Example 5)
The glass frit having an average particle size of 3 μm of Example 5 was pulverized with a bead mill until the size was about the same as that of Ni powder to obtain a glass frit of 0.5 μm. Using this glass frit and the Ni powder of Example 2, a paste having the following composition was prepared by the procedure of Example 2.
Ni: Ethyl cellulose: Oleic acid: Tarpineol: Glass frit = 73: 2.2: 1.6: 22.2: 1.0

(Example 7: Preparation of Ni powder paste for external electrode 7) (Example 6)
The glass frit having an average particle size of 3 μm of Example 5 was pulverized with a bead mill until the size was about the same as that of Ni powder to obtain a glass frit of 0.5 μm.
Ni powder was obtained according to the procedure of Example 2 except that the diaminosilane of Example 3 was used as a titanate coupling agent KR-44. The 1% volumetric shrinkage temperature at TMA was 850 ° C.
Using this glass frit and this Ni powder, a paste having the following composition was prepared by the procedure of Example 2.
Ni: Ethyl cellulose: Oleic acid: Tarpineol: Glass frit = 73: 2.2: 1.6: 22.2: 1.0

(Example 8: MLCC cycle test)
The laminate prepared in Example 1 was cut into a length of 0.4 mm and a width of 0.2 mm, immersed in the pastes of Examples 2 to 7, baked at 510 ° C. in the air, and then N ₂ containing 2% H ₂ . It was calcined at 850 ° C. Then, chelate Sn plating at pH 4.5 was performed to form a Sn plating layer having a thickness of 3 μm on the fired body. The cross section of the MLCC was observed by SEM, and the thicknesses of the Ni layer and the Sn layer were measured.
After that, MLCC and Sn-3.0 wt% Ag-0.5 wt% Cu solder paste (solder powder particle size 20 to 32 μm) produced on a Cu pad formed by electrolytic plating on polyimide were used at 250 ° C. Joined. After that, 1000 cycles were repeated with −55 ° C./15 minutes ⇔ 125 ° C./15 minutes as one cycle. At each stage, the share strength of the MLCC and the substrate was measured. In measuring the share strength, the tool was set at a height of 50 μm from the substrate so that the tool would hit the MLCC. The moving speed of the tool was set to 300 μms ^-1 .

(Example 9: Conventional external electrode Cu paste) (Reference example 1)
A Cu paste for an external electrode was prepared according to JP-A-2002-277372. That is, 60 kg of copper sulfate pentahydrate was dissolved in 80 L of water at 50 ° C., and 16 kg of 25 wt% ammonia water was gradually added dropwise while maintaining the liquid temperature at 50 ° C. Then, 120 L of hydrazine monohydrate and 15 liters of aqueous ammonia were added at the same time. The produced precipitate was decanted with pure water at 50 ° C. to precipitate, and 6 kg of hydrazine monohydrate was added thereto to produce 15 kg of Cu powder. This was suction-filtered, surface-treated with oleic acid, dried at 70 ° C. in a vacuum dryer, and the cake was crushed to obtain surface-treated copper powder. The Cu powder, glass frit, ethyl cellulose, and turpineol were mixed so as to have the following composition, and 5 passes were passed through 3 rolls with a roll gap of 5 μm to obtain a Cu paste for an external electrode.
Cu: Glass frit: Ethyl cellulose: Tarpineol = 75: 5: 1: 4: 18.6
This paste was immersed in the laminate according to the procedure of Example 8, fired, Ni-plated in a Watt bath, and then chelated tin-plated with a weak acid.

(Example 10: Preparation of Ni powder paste for external electrode 9) (Comparative Example 1)
The glass frit having an average particle size of 3 μm of Example 5 was pulverized with a bead mill until the size was about the same as that of Ni powder to obtain a glass frit of 0.5 μm. Using this glass frit and the Ni powder of Example 2, a paste having the following composition was prepared by the procedure of Example 2.
Ni: Ethyl cellulose: Oleic acid: Tarpineol: Glass frit = 73: 2.2: 1.6: 18.2: 5.0

(Example 11: Observation of calcined Ni layer)
The Ni layer is not formed by firing Ni powder. Except for Reference Example 1, the cross-section of the external electrode of each MLCC is processed, and the concentration of Si, which is the main component of the glass frit, in the fired Ni layer is mapped by EPMA by cross-section observation. I asked for it. Observation was performed with SU-70 manufactured by Hitachi Ha Technology, and EPMA mapping was performed at an acceleration voltage of 10 kV. First, the thickness of the fired Ni layer was obtained at a low magnification, and mapping was performed at a magnification at which 60 to 80% of the thickness entered the screen. This was analyzed in a range of 30 times the thickness of the fired Ni layer in the vertical direction, and the concentration of Si, which is the main component of the glass frit, in the fired Ni layer was determined. As a magnification at the time of analysis, it is desirable that 60 to 80% of the thickness of the fired Ni layer enters the analysis screen. If it exceeds 80%, the thickness of the fired Ni layer itself varies, and if Si is contained in the underlying ceramic prime field, the analysis value may include this. If it is less than 60%, it is possible that a specific range in the Ni layer is being analyzed, which is not preferable for the evaluation of the fired Ni layer.

In Examples 1 to 4, the thickness of the external electrode and the plating is very thin as compared with Reference Example 1 of the conventional MLCC. While the share strength after mounting was the same as that of the conventional product, in the comparative example, Sn plating failure occurred probably because of the glass frit of the fired Ni layer, and the share strength could not be obtained.

The present invention provides a laminated ceramic product, particularly an external electrode of MLCC, which is a thinned external electrode while maintaining the adhesion to the laminate required for the external electrode. The present invention is an industrially useful invention.
[Preferable embodiment]
The present invention includes the following (1) embodiments.
(1)
An external electrode provided on a ceramic laminate,
It consists of a Ni layer provided on the laminated end face of the ceramic laminate and a Sn plating layer provided on the Ni layer.
The Ni layer has a thickness of 1 to 20 μm and has a thickness of 1 to 20 μm.
An external electrode having a Si content of 0.05% by mass or more and less than 0.68% by mass in the Ni layer with respect to the Ni content.
(2)
The external electrode according to (1), wherein the Sn plating layer has a thickness of 0.5 to 10 μm.
(3)
The external electrode according to any one of (1) to (2), wherein the Ni layer is a fired Ni layer formed by firing Ni paste.
(4)
The external electrode according to any one of (1) to (3), wherein the ceramic laminate is a ceramic laminate in which an internal electrode layer and a ceramic layer are laminated.
(5)
A laminated ceramic product in which the external electrode according to any one of (1) to (4) is provided on the laminated end face of the ceramic laminate.
(6)
The ceramic laminate is a rectangular parallelepiped shape,
A laminated ceramic product in which the external electrodes according to any one of (1) to (5) are provided on two facing surfaces of the laminated end faces of the ceramic laminate.
(7)
The laminated ceramic product according to (6), wherein the laminated ceramic product is a laminated ceramic capacitor or a laminated ceramic inductor.

Claims (13)

An external electrode provided on a ceramic laminate,
It consists of a Ni layer provided on the laminated end face of the ceramic laminate and a Sn plating layer provided on the Ni layer.
The Ni layer has a thickness of 1 to 20 μm and has a thickness of 1 to 20 μm.
In the Ni layer, the Si content with respect to the Ni content is 0.05% by mass or more and less than 0.68% by mass.
The Ni layer is a fired Ni layer formed by firing Ni paste.
An external electrode in which the Ni powder of the Ni paste is a Ni powder surface-treated with a silane coupling agent . The external electrode according to claim 1, wherein the thickness of the Sn plating layer is 0.5 to 10 μm. The external electrode according to any one of claims 1 to 2, wherein the silane coupling agent is a silane coupling agent having an amino group . The external electrode according to any one of claims 1 to 3, wherein the ceramic laminate is a ceramic laminate in which an internal electrode layer and a ceramic layer are laminated. A laminated ceramic product comprising the external electrode according to any one of claims 1 to 4 provided on the laminated end face of the ceramic laminate. The ceramic laminate is a rectangular parallelepiped shape,
A laminated ceramic product, wherein the external electrodes according to any one of claims 1 to 5 are provided on two facing surfaces of the laminated end faces of the ceramic laminate. The laminated ceramic product according to claim 6, wherein the laminated ceramic product is a laminated ceramic capacitor or a laminated ceramic inductor. It is a method of manufacturing an external electrode provided on a ceramic laminate.
The external electrodes provided on the ceramic laminate are
It consists of a Ni layer provided on the laminated end face of the ceramic laminate and a Sn plating layer provided on the Ni layer.
The Ni layer has a thickness of 1 to 20 μm and has a thickness of 1 to 20 μm.
In the Ni layer, the Si content with respect to the Ni content is 0.05% by mass or more and less than 0.68% by mass.
The Ni layer is a fired Ni layer formed by firing a Ni paste at a temperature of 850 ° C. or higher.
The Ni powder of the Ni paste is a Ni powder having a sintering start temperature of 600 ° C. or higher.
A method for manufacturing an external electrode, wherein the Ni powder of the Ni paste is a Ni powder surface-treated with a silane coupling agent. The manufacturing method according to claim 8, wherein the thickness of the Sn plating layer is 0.5 to 10 μm. The manufacturing method according to any one of claims 8 to 9, wherein the ceramic laminate is a ceramic laminate in which an internal electrode layer and a ceramic layer are laminated. A method for manufacturing a laminated ceramic product, comprising a step of providing an external electrode on a laminated end face of the ceramic laminate by the method for manufacturing an external electrode according to any one of claims 8 to 10. The ceramic laminate is a rectangular parallelepiped shape,
The manufacturing method according to claim 11, further comprising a step of providing external electrodes on two facing surfaces of the laminated end faces of the ceramic laminate. The manufacturing method according to any one of claims 11 to 12, wherein the monolithic ceramic product is a monolithic ceramic capacitor or a monolithic ceramic inductor.