JPH11111564A - Cr composite electronic component and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CR composite electronic component and its production method by which a CR or (L/C) R series circuit can be obtained easily at a low cost, through a simplified production step without special conditions for baking, and the resistance values are easily controlled. SOLUTION: A dielectric layer 2 and an inner electrode 3 are laminated alternately, and the inner electrode 3 is connected electrically with l terminal electrodes formed on the end of a CR composite electronic component such that they function as a capacitor. At least one terminal electrode is provided with first to third electrode layers in sequence from the inner electrode side, and the first electrode layer 4 contains one or two elements from among Fe, Co, Cu and Ni. A second electrode layer 5 has an oxide of the first electrode layer, and a third electrode layer 6 contains one or two elements or from among Ag, Au, Pt, Pd, Rh, Ir, and Ru.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a CR composite electronic component in which a resistance or impedance element is added to a multilayer capacitor having a nonmagnetic ceramic dielectric layer.

[0002]

2. Description of the Related Art At present, switching power supplies and DC-DC converters are used for many power supplies of electronic devices. There is a power supply bypass capacitor as a capacitor used for these power supplies. As the power supply bypass capacitor, a low-capacity multilayer ceramic capacitor and a high-capacity electrolytic capacitor such as aluminum or tantalum have been used in accordance with the power supply capacity, switching frequency, and circuit parameters such as a smoothing coil used in combination. By the way, an electrolytic capacitor can easily obtain a large capacity and has an excellent surface as a power supply bypass (smoothing) capacitor. However, it is large, has poor low-temperature characteristics, may cause a short circuit, and has an internal impedance. Is relatively high,
Loss due to equivalent series resistance (ESR) occurs constantly,
There is a problem that heat is generated as a result, frequency characteristics are poor, and smoothness is deteriorated. In recent years,
With the technological innovation, the capacitance of the multilayer ceramic capacitor is approaching the capacitance of the electrolytic capacitor with the progress of thinning of the dielectric and internal electrodes of the multilayer ceramic capacitor and the development of the lamination technology. For this reason, various attempts have been made to replace electrolytic capacitors with multilayer ceramic capacitors.

In a bypass capacitor of a power supply, ripple noise is important as a factor showing a smoothing action. How much the ripple noise is suppressed depends on the equivalent series resistance (ESR) of the capacitor. Here, assuming that the ripple voltage is ΔVr, the current flowing through the choke coil is Δi, and the equivalent series resistance is ESR, then ΔVr = Δi × ESR. Therefore, it is preferable to use a capacitor having a low ESR in a bypass circuit of a power supply, and an attempt has been made to use a multilayer ceramic capacitor having a low ESR in a power supply circuit.

However, in a secondary circuit such as a DC-DC converter or a switching power supply having a feedback circuit, the ESR of the smoothing circuit has a great effect on the phase characteristics of the feedback loop, and a problem occurs particularly when the ESR becomes extremely low. Sometimes. That is, when a multilayer ceramic capacitor having a low ESR is used as the smoothing capacitor, the secondary-side smoothing circuit is equivalently composed of only the L and C components, and the phase components existing in the circuit are ± 90 ° and 0 °. ° only, there is no phase margin, and oscillation occurs easily. A similar phenomenon appears as an oscillation phenomenon at the time of a load change even in a power supply circuit using a three-terminal regulator.

For this reason, various so-called CR composite electronic components in which a resistance component is added to a multilayer ceramic capacitor have been proposed. For example, Japanese Patent Application Laid-Open No. H8-45784 describes a composite electronic component in which an end of a multilayer ceramic capacitor is formed into a semiconductor using a carbide and a reducing agent. However, the manufacturing method is to apply a paste for external electrodes to the multilayer ceramic capacitor body, temporarily calcine the paste in a reducing atmosphere, carbonize the binder and leave it, and then bake it at 700 to 750 ° C. The carbide is made to act as a reducing agent to form a semiconductor. The resistance value is controlled by the amount of the reducing agent. However, in this method, the process of forming a semiconductor is complicated, and if the process of forming a terminal electrode is included, heat treatment is required three times, resulting in reduced productivity and increased energy cost.
Moreover, since the resistance value is controlled by the amount of the reducing agent, it is difficult to obtain a desired value accurately, circuit design becomes difficult, and there are many variations between products. Yield is poor.

[0006] For example, see Japanese Patent Application Laid-Open No. Sho 59-225509.
As described in Japanese Patent Application Laid-Open Publication No. H11-107, there is known a multilayer ceramic capacitor in which a resistor paste such as ruthenium oxide is further laminated and fired simultaneously to form a resistor. However, when the terminal electrode is provided as it is, an equivalent circuit becomes a parallel circuit of C / R or (LC) / R, and a series circuit cannot be obtained. Further, in order to obtain a series circuit, the shape of the terminal electrode is complicated, and the manufacturing process is also complicated.

[0007] Japanese Patent No. 2578264 discloses a CR composite component in which a metal oxide film is provided on the surface of an external electrode to obtain a desired equivalent series resistance. However, in the CR composite component described in the example of the publication, a nickel terminal electrode is heated to form a metal oxide film, and the resistance value is adjusted by barrel polishing. It is done by adjusting. For this reason, it is difficult to obtain a desired resistance value, and adjustment of the resistance value is complicated, resulting in poor mass productivity. Also, on the formed metal oxide film,
Furthermore, the nickel layer is provided by electroless plating,
In this method, it is necessary to provide a mask so that plating does not adhere to portions other than the terminal portions, and the number of manufacturing steps increases. Further, the adhesion between the nickel plating and the metal oxide film is poor, and when a lead wire is provided on the nickel plating, the lead wire is easily peeled off.

Although there is a method of connecting a resistor in series with the smoothing capacitor, it is expensive and not practical.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a CR or (L / C) R series circuit that does not require special firing conditions, has a simple manufacturing process, has a low production cost, and has a simple structure. An object of the present invention is to provide a CR composite electronic component in which the resistance value is easily controlled and the bonding strength of the lead wire is strong, and a method for manufacturing the same.

[0010]

The above object is achieved by the following constitutions (1) to (12). (1) Dielectric layers and internal electrodes are alternately stacked, and the internal electrodes and terminal electrodes formed at the ends of the CR composite electronic component are electrically connected so as to function as capacitors, At least one of the terminal electrodes has first to third electrode layers sequentially from the internal electrode side, and the first electrode layer is formed of Fe,
Containing one or more of Co, Cu and Ni,
The second electrode layer contains the oxide of the first electrode layer, and the third electrode layer contains a CR composite containing one or more of Ag, Au, Pt, Pd, Rh, Ir and Ru. Electronic components. (2) The second electrode layer is made of FeO, α as an oxide.
—Fe ₂ O ₃ , γ-Fe ₂ O ₃ , Fe ₃ O ₄ , CoO, C
The CR composite electronic component according to the above (1), containing one or more of o ₃ O ₄ , Cu ₂ O, Cu ₃ O ₄ , CuO, and NiO. (3) The first electrode layer is made of Ag, Au, Pt, P
one or more of d, Rh, Ir and Ru
The CR composite electronic component according to any one of the above (1) and (2), which contains not more than wt%. (4) The first to third electrode layers are made of glass of 0 to 20.
The CR composite electronic component according to any one of the above (1) to (3), which contains wt%. (5) The CR composite electronic component according to any one of (1) to (4) above, wherein the equivalent circuit has a CR or (LC) R series circuit. (6) The above (1) to (1), wherein the internal electrode layer contains Ni.
The CR composite electronic component according to any one of (5). (7) The CR composite electronic component according to any one of (1) to (6), further including a plating layer outside the terminal electrode. (8) Dielectric layers and internal electrode layers are alternately stacked to form a green chip, which is fired to form a chip body,
A paste for the first electrode layer is applied to the chip body, and baked in a neutral or reducing atmosphere to form precursors for the first and second electrode layers. A paste is applied and baked in an oxidizing atmosphere to oxidize the vicinity of the interface between the precursor of the first and second electrode layers and the third electrode layer, thereby forming the first to third electrodes. A CR for forming a layer to obtain a CR composite part according to any one of the above (1) to (8)
Manufacturing method of composite electronic components. (9) The CR composite electronic component according to (8), wherein the first electrode layer paste or the second electrode layer paste has metal particles having an average particle diameter of 0.1 to 10 μm. (10) Dielectric layers and internal electrode layers are alternately laminated to form a green chip, which is baked to form a chip body, and a paste for a first electrode layer is applied to the chip body;
Further, a third electrode layer paste is applied thereon and fired in a neutral or reducing atmosphere. During the cooling process, the third electrode layer paste is turned into an oxidizing atmosphere to form a third electrode layer paste fired body. A method of manufacturing a CR composite electronic component in which the vicinity of the interface with the electrode layer is oxidized to form the first, second, and third electrode layers to obtain the CR composite component according to any one of (1) to (7) above. . (11) Dielectric layers and internal electrode layers are alternately laminated to form a green chip, a first electrode layer paste is applied to the green chip, and a third electrode layer paste is further applied thereon. Is applied, baked in a reducing atmosphere, and oxidized during the cooling process to oxidize the vicinity of the interface with the third electrode layer of the first electrode layer paste fired body,
A method of manufacturing a CR composite electronic component, wherein the green chip, the first, second, and third electrode layers are formed to obtain the CR composite component according to any one of (1) to (7). (12) The first electrode layer contains Ni, and the third electrode layer contains one or more of Pd, Pt, Rh, Ir and Ru, and is a CR composite of the above (10) or (11). Manufacturing method of electronic components.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The CR composite electronic component of the present invention has a structure in which dielectric layers and internal electrodes are alternately laminated, and the internal electrodes and terminal electrodes formed at the ends of the CR composite electronic component. Are electrically connected so as to form a capacitor. At least one of the terminal electrodes has first to third electrode layers sequentially from the internal electrode side, and the first electrode layer is made of Fe, Co, Cu and Ni. The second electrode layer contains the oxide of the first electrode layer, and the third electrode layer contains one of Ag, Au, Pt, Pd, Rh, Ir and Ru. Contains two or more species. Thus, the terminal electrode is
By forming the second electrode layer using an oxide of the first electrode layer as a layer structure, the second electrode layer having a high resistance becomes a resistance component which is equivalently connected in series to the capacitor, and the equivalent of the capacitor is obtained. It becomes a CR composite electronic component in which the series resistance (ESR) is controlled.

The first electrode layer is made of Fe, Co, Cu and N
i, containing one or more kinds, preferably Cu, N
i and Cu-Ni alloys. In addition to these first electrode layer metals, Ag, Au, Pt, Pd, R
Metals such as h, Ir and Ru, particularly Ag, may be contained preferably in an amount of about 10% by weight or less, more preferably about 5% by weight or less. When these metals are added to the first electrode layer metal, it is not necessary to add them in a powder state. The first electrode layer metal particles may be coated with these metals, or the first electrode metal may be added. Metals for layers and functionally graded powders of these metals may be used.

The average particle diameter of the metal for the first electrode layer is preferably 0.01 to 100 μm, particularly 0.1 to 30 μm.
Is preferable. When the particle size of the first electrode layer metal is smaller than the above range, when a plurality of types of metals are used, the aggregation of the metals becomes intense, and it becomes difficult for the metal components to completely dissolve during firing. If the particle size of the first electrode layer metal is larger than the above range, it becomes difficult to form a paste.

The method for forming the first electrode layer or a precursor thereof is not particularly limited, but is usually a dipping method, a screen printing method, a transfer method, or a dry plating method, and the dipping method is particularly preferable. . Although the thickness of the first electrode to be formed is not particularly limited, it is generally preferably 5 to 100 μm, particularly preferably about 10 to 80 μm.

In order to provide the first electrode layer or its precursor by a dipping method or the like, a paste obtained by kneading the metal for the first electrode layer and an organic vehicle may be used. The terminal electrode paste usually contains a glass frit as an inorganic binder, an organic binder, and a solvent in addition to the metal for the first electrode layer. The content of the metal for the first electrode layer of the terminal electrode paste is preferably from 50 to
The range is preferably 90% by weight, more preferably about 60 to 80% by weight.

The third electrode layer is formed of Ag, Au, Pt, Pd, Rh, Ir, and R as third electrode layer metals.
It contains one or more kinds of u, preferably Ag or Pt, Pd, and particularly preferably contains Ag. The method for forming the third electrode layer may be similar to that of the first electrode layer. The thickness of the third electrode to be formed is not particularly limited, but is usually 5 to 100 μm, particularly 10 to 50 μm.
The degree is preferred. The third electrode layer prevents excessive oxidation of the first electrode layer and improves the plating property. If the first electrode layer is excessively oxidized, the capacity is reduced, and the function as a capacitor is significantly reduced.

The average particle size of the metal for the third electrode layer is preferably in the range of 0.01 to 100 μm, particularly preferably in the range of 1 to 30 μm. When the particle size of the third electrode layer metal is smaller than the above range, when a plurality of types of metals are used, the aggregation of the metals becomes severe, and the metal components are hardly completely dissolved during firing. If the particle size of the third electrode layer metal is larger than the above range, it becomes difficult to form a paste.

The method for forming the third electrode layer may be the same as that for the first electrode layer. Although the thickness of the third electrode to be formed is not particularly limited, it is generally preferably 5 to 100 μm, particularly preferably about 10 to 80 μm.

In order to provide the third electrode layer by a dipping method or the like, it is sufficient to conform to the case of the first electrode layer. The content of the metal for the first electrode layer in the terminal electrode paste is preferably 50 to 95 wt%, more preferably 60 to 90 wt%.
The range of the degree is preferable.

The first electrode layer and the third electrode layer contain glass for assisting adhesion to the element and sintering of the conductive material. Such a glass is not particularly limited, but when used for the first electrode layer, it may be fired in a reducing or neutral atmosphere, so long as it functions as a glass even in such an atmosphere. . For example, silicate glass (SiO ₂ : 20-80 wt%, Na ₂ O: 80)
２０20 wt%), borosilicate glass (B ₂ O ₃ : 5-50 w
_{t%, SiO 2: 5~70wt%} , PbO: 1~10wt
_{%, K 2 O: 1~15wt%} ), alumina silicate glass _{(Al 2 O 3: 1~30wt%} , SiO 2: 10~60wt
_{%, Na 2 O: 5~15wt%} , CaO: 1~20wt%,
B ₂ O _3: 5~30wt%) of the glass frit is selected from may be used one or two or more. If necessary, CaO: 0.01 to 50% by weight, SrO: 0.
01 to 70 wt%, BaO: 0.01 to 50 wt%, Mg
O: 0.01 to 5 wt%, ZnO: 0.01 to 70 wt%,
_{PbO: 0.01~5wt%, Na 2 O} : 0.01~10w
_{t%, K 2 O: 0.01~10wt} %, MnO 2: 0.0
An additive such as 1 to 20% by weight may be mixed and used so as to have a predetermined composition ratio. These may be added in a total of 50 wt% or less. Although the content of glass is not particularly limited, usually, in the case of the first electrode layer, it is 0.5 to 20% by weight, preferably about 0.5 to 15% by weight with respect to the metal component, and the third electrode layer In the case of a layer, 0 to 20 wt.
%, Preferably about 0.5 to 15% by weight. The third electrode layer may not have glass. The average particle size of the glass frit is preferably about 0.01 to 30 μm. If the average particle size of the glass frit is smaller than the above range, the glass is strongly agglomerated, resulting in a local sintering effect of the conductive material, which causes a crack in the terminal electrode. When the average particle size is larger than the above range, the dispersion of the glass becomes worse, and the solid solution of the metal is suppressed,
The adhesiveness between the terminal electrode and the chip body decreases.

The organic binder is not particularly limited, and may be appropriately selected from those commonly used as binders for ceramic materials. Examples of such an organic binder include ethyl cellulose, acrylic resin, and butyral resin, and examples of the solvent include terpineol, terpineol, butyl carbitol, kerosene, and the like. The content of the organic binder and the solvent in the paste is not particularly limited, and may be a commonly used amount, for example, about 1 to 5% by weight of the organic binder and about 10 to 50% by weight of the solvent.

Further, in the first and third electrode layer pastes, various dispersants, plasticizers,
Additives such as dielectrics and insulators may be contained. The total content of these is preferably 10% by weight or less.

The second electrode layer is formed by oxidizing the first electrode layer metal contained in the first electrode layer (a precursor of the first and second electrode layers). That is, it is a metal oxide containing layer. A third electrode layer is formed on the first electrode layer, and the third electrode layer is baked in an oxidizing atmosphere to oxidize the vicinity of the surface of the first electrode layer, thereby forming a high-resistance second electrode layer. You. Therefore, at least the second electrode layer and the third electrode layer are fired at the same time.

The oxide present in the second electrode layer is
As described above, the metal oxide contained in the first electrode layer is an oxide of the metal, but it is not necessary that all the metal is oxidized, and a part of the metal may be oxidized. In this case, the oxide is preferably at least 10 at%, more preferably 25 at%, in terms of oxygen, based on the total metal content in the second electrode layer.
It is preferable that it is contained above. The thickness of the formed second electrode layer is not particularly limited and may be appropriately adjusted depending on a desired ESR.
0 μm, particularly preferably about 0.05 to 30 μm. Note that the first electrode layer (a precursor of the first and second electrode layers)
Is oxidized, so that the metal or glass for the third electrode layer is also present in the second electrode layer. The ESR obtained by the second electrode layer is preferably 1 to 2000 mΩ, particularly preferably about 10 to 1000 mΩ. The presence of the oxide can usually be determined by X-ray diffraction, and its composition can be determined by EPMA or the like.

By such oxidation, Cu is replaced by Cu
One or two or more of ₂ O, Cu ₃ O ₄ , CuO, etc. are generated, and NiO is usually generated with Ni. These oxides may deviate somewhat from the stoichiometric composition. The third
Ag, Au, Pt, Pd, Rh,
Ir and Ru are not normally oxidized.

As for the terminal electrode, either one of the electrodes may have the above structure to increase the resistance, or both may have the higher resistance. Further, the resistance value of the terminal electrode can be adjusted by adjusting the oxide or the minimum thickness of the second electrode layer.
In the case where both terminal electrodes have a high resistance, the resistance value is the sum of the resistance values of the respective electrodes.

<Plating Layer> It is preferable to provide a plating layer on the outside of the terminal electrode, that is, on the terminal side. The plating layer includes nickel, tin, solder and the like, and is preferably composed of a nickel plating layer and a tin or tin-lead alloy solder layer. As for the plating layer, a nickel plating layer is formed on the terminal electrode side, and as a material outside the nickel plating layer, a material having low resistivity and good solder wettability is preferable,
Tin or tin-lead alloy solder is preferred, and particularly preferred is one provided with tin-lead alloy solder.
The plating layer improves the solder wettability when attaching the lead wire, ensures the connection between the terminal electrode and the lead wire, and is formed so as to cover the entire terminal electrode. Becomes stable.

The method for forming the plating layer is not particularly limited, and dry plating using a sputtering method or a vapor deposition method is also possible, but a conventionally known electrolytic plating method or electroless plating method is used. It is preferable because it can be easily provided by wet plating. When a wet method is used, it is preferable to use an electrolytic plating method since a nickel plating layer is formed on a terminal electrode. Also, tin or tin - lead alloy solder layer may be Electrolytic plating using either method for the nickel layer is a metal film is formed is preferable. The thickness of the plating layer is preferably 0.1 to 30.
It is preferably about μm.

<Dielectric Layer> The dielectric material constituting the dielectric layer is not particularly limited, and various dielectric materials may be used. For example, a titanium oxide-based or titanate-based composite oxide may be used. Or a mixture thereof is preferable. As the titanium oxide-based material, NiO, Cu
TiO ₂ or the like containing a total of about 0.001 to 30 wt% of O, Mn ₃ O ₄ , Al ₂ O ₃ , MgO, SiO _2, etc. is used as the titanate-based composite oxide, and barium titanate BaTiO _{3 is used.}
And the like. The atomic ratio of Ba / Ti is 0.95-
It is preferably about 1.20, and BaTiO ₃ contains MgO, Ca
O, Mn ₃ O ₄ , Y ₂ O ₃ , V ₂ O ₅ , ZnO, ZrO ₂ , N
_{b 2 O 5, Cr 2 O} 3, Fe 2 O 3, P 2 O 5, SrO, Na 2
O, K ₂ O and the like may be contained in a total amount of about 0.001 to 30% by weight. Further, glass such as (BaCa) SiO ₃ glass or the like may be contained for adjusting the firing temperature, the coefficient of linear expansion, and the like.

The thickness of one dielectric layer is not particularly limited, but is usually about 5 to 20 μm. The number of stacked dielectric layers is usually about 2 to 300.

<Internal Electrode Layer> Although the conductive material contained in the internal electrode layer is not particularly limited, an inexpensive base metal or the like can be used by using a material having reduction resistance as the dielectric layer constituting material. preferable. As the metal used as the conductive material, Ni or a Ni alloy is preferable. As the Ni alloy, an alloy of one or more elements selected from Mn, Cr, Co, Al, and the like and Ni is preferable, and the Ni content in the alloy is preferably 95 wt% or more.

Incidentally, various trace components such as P may be contained in Ni or Ni alloy in an amount of about 0.1 wt% or less.

The thickness of the internal electrode layer may be appropriately determined according to the application and the like, but is usually 0.5 to 5 μm, especially 0.5 to 5 μm.
It is preferably about 2.5 μm.

Next, a method of manufacturing a CR composite electronic component according to the present invention will be described.

The CR composite electronic component of the present invention is manufactured by manufacturing a green chip by a normal printing method or sheet method using a paste, printing or transferring a resistor paste on at least one end of the chip, and simultaneously firing the chip. Can be manufactured.

<Dielectric Layer Paste> The dielectric layer paste is manufactured by kneading a dielectric material and an organic vehicle.

As the dielectric material, a powder according to the composition of the dielectric layer is used. The method for producing the dielectric material is not particularly limited. For example, when barium titanate is used as the titanate-based composite oxide, BaTi synthesized by a hydrothermal synthesis method or the like is used.
A method of mixing an auxiliary component material with O ₃ can be used. Further, a dry synthesis method in which a mixture of BaCO ₃ , TiO _2, and auxiliary component raw materials is calcined to cause a solid phase reaction may be used, or a hydrothermal synthesis method may be used. In addition, coprecipitation method, sol
It may be synthesized by calcining a mixture of the precipitate obtained by the gel method, alkali hydrolysis method, precipitation mixing method or the like and the raw material of the auxiliary component. In addition, as the auxiliary component raw materials, oxides, various compounds that become oxides by firing, for example, carbonates, oxalates,
At least one of nitrates, hydroxides, organometallic compounds and the like can be used.

The average particle size of the dielectric raw material may be determined according to the target average crystal grain size of the dielectric layer. Usually, a powder having an average particle size of about 0.3 to 1.0 μm is used.

The organic vehicle is obtained by dissolving a binder in an organic solvent. The binder used for the organic vehicle is not particularly limited, and may be appropriately selected from various ordinary binders such as ethyl cellulose. In addition, the organic solvent to be used is not particularly limited, and may be appropriately selected from various organic solvents such as terpineol, butyl carbitol, acetone, and toluene according to a method to be used such as a printing method and a sheet method.

<Paste for Internal Electrode Layer> The paste for the internal electrode layer is composed of the above-mentioned various conductive metals and alloys, or various oxides, organometallic compounds, resinates and the like which become the above-mentioned conductive materials after firing, and It is prepared by kneading with a vehicle.

<Paste for Terminal Electrode> The paste for terminal electrode may be prepared in the same manner as the paste for internal electrode layer described above.

<Organic Vehicle Content> There is no particular limitation on the content of the organic vehicle in each of the above-mentioned pastes.
It may be about 0 to 50 wt%. Further, each paste may contain additives selected from various dispersants, plasticizers, dielectrics, insulators, and the like, as necessary. It is preferable that the total content thereof be 10 wt% or less.

<Preparation of Green Chip> In the case of using a printing method, a paste for a dielectric layer and a paste for an internal electrode layer are laminated and printed on a substrate such as PET. At this time, the layers are laminated such that one end of the internal electrode paste is alternately exposed to the outside from the end of the dielectric layer paste. Thereafter, the chip is cut into a predetermined shape to form a chip, and is separated from the substrate to form a green chip.

When the sheet method is used, a green sheet is formed using the dielectric layer paste, and the internal electrode layer paste is alternately formed on the green sheet, and the end of the internal electrode paste is alternately formed on the dielectric layer. Those printed so as to be exposed from one end of the paste for use are laminated and cut into a predetermined shape to obtain a green chip.

<Binder Removal Step> The conditions of the binder removal treatment performed before firing may be ordinary conditions. However, when a base metal such as Ni or a Ni alloy is used as the conductive material of the internal electrode layer, the following conditions are particularly preferable. It is preferable to carry out in. Heating rate: 5 to 300 ° C / hour, especially 10 to 100 ° C / hour
Time Holding temperature: 200 to 400 ° C, especially 250 to 300 ° C Temperature holding time: 0.5 to 24 hours, especially 5 to 20 hours Atmosphere: in air

<Firing Step> The atmosphere at the time of firing the green chip may be appropriately determined according to the type of the conductive material in the internal electrode layer paste, but when a base metal such as Ni or a Ni alloy is used as the conductive material, The firing atmosphere is preferably a mixture of N ₂ as a main component, and H ₂ 1 to 10% mixed with H ₂ O gas obtained by steam pressure at 10 to 35 ° C.
The oxygen partial pressure is preferably set to 10 ^-8 to 10 ^-12 atm. If the oxygen partial pressure is less than the above range, the conductive material of the internal electrode layer may abnormally sinter and be interrupted. If the oxygen partial pressure exceeds the above range, the internal electrode layer tends to be oxidized.

The holding temperature during firing is 1100 to 1400
° C, particularly preferably 1200 to 1300 ° C.
When the holding temperature is lower than the above range, the densification is insufficient, and when the holding temperature is higher than the above range, the internal electrode is easily broken. Further, the temperature holding time during firing is 0.5 to 8 hours,
Particularly, 1 to 3 hours is preferable.

<Annealing Step> When firing in a reducing atmosphere, it is preferable to anneal the CR composite electronic component chip body. Annealing is a process for reoxidizing the dielectric layer, which can significantly increase the IR accelerated life.

The oxygen partial pressure in the annealing atmosphere is preferably 10 ⁻⁶ atm or more, particularly preferably 10 ⁻⁵ to 10 ⁻⁸ atm. When the oxygen partial pressure is less than the above range, it is difficult to reoxidize the dielectric layer, and when the oxygen partial pressure exceeds the above range, the internal electrode layer tends to be oxidized.

The holding temperature at the time of annealing is preferably 1100 ° C. or less, particularly preferably 500 to 1000 ° C. If the holding temperature is less than the above range, the oxidation of the dielectric layer tends to be insufficient and the life tends to be short, and if the holding temperature exceeds the above range, the internal electrode layer is oxidized and the capacity is reduced, It tends to react with the substrate and shorten its life. Note that the annealing step may be configured only by raising and lowering the temperature. In this case, the temperature holding time is zero, and the holding temperature is synonymous with the maximum temperature. The temperature holding time is
0-20 hours, especially 2-10 hours are preferred. It is preferable to use a humidified N ₂ gas or the like as the atmosphere gas.

In each of the above-described steps of binder removal, baking, and annealing, for example, a wetter may be used to humidify N ₂ , H ₂ , a mixed gas, and the like. In this case, the water temperature is preferably about 5 to 75 ° C.

The binder removing step, firing step, and annealing step may be performed continuously or independently.

In the case where these steps are continuously performed, after removing the binder, the atmosphere is changed without cooling, the temperature is raised to the holding temperature for firing, firing is performed, and then cooling is performed. It is preferable to perform the annealing while changing the atmosphere when the temperature reaches.

When these steps are performed independently, in the binder removal processing step, the temperature is raised to a predetermined holding temperature, held for a predetermined time, and then lowered to room temperature. At that time, the atmosphere for removing the binder is the same as in the case where the process is performed continuously.
Further, in the annealing step, the temperature is raised to a predetermined holding temperature,
After holding for a predetermined time, the temperature is lowered to room temperature. The annealing atmosphere at that time is the same as in the case of performing the annealing continuously. Further, the binder removal step and the firing step may be performed continuously, and only the annealing step may be performed independently. Only the binder removal step may be performed independently, and the firing step and the annealing step may be performed continuously. You may do so.

<Formation of Terminal Electrode> The paste for the first electrode layer is printed or transferred onto the chip body obtained as described above and baked to form a terminal (external) electrode. The firing conditions for the first electrode layer paste are, for example, 1-600 ° C. and 800 ° C. in a reducing atmosphere such as a mixed gas of N ₂ and H _2.
It is preferable to set it for about one minute to one hour. Then the third
The electrode layer paste is printed or transferred, and the third electrode layer is fired. The firing conditions for the third electrode layer paste are as follows:
For example, it is preferable that the heating time is about 0 minute to 1 hour at 400 to 850 ° C. in an oxidizing atmosphere such as air. On this occasion,
A second electrode layer is formed near the interface between the first electrode layer paste and the third electrode layer paste.

Note that Ni is used as a main component for the first electrode layer, and Pd, Pt, Rh, Ir and R are used for the third electrode layer.
When u is used as a main component, the first electrode layer and the third electrode layer can be simultaneously fired. At this time, one or two or more of Fe, Co and Cu are added to the first electrode layer for three times.
0 wt% or less, and the third electrode layer
g and / or Au may be contained in an amount of 20 wt% or less. In this case, the first electrode layer paste and the third electrode layer paste may be printed or transferred to the dielectric green chip on which the internal electrodes are laminated and fired simultaneously.
As firing conditions in this case, first, firing is performed under the above-described green chip firing conditions, and in the cooling process, firing is performed at 800 to 400 ° C. for about 1 minute to 1 hour as an oxidizing atmosphere. Also in these cases, the second electrode layer paste is placed near the interface with the third electrode layer paste,
Is formed.

<Plating Step> Further, the chip body on which the terminal electrodes are formed is immersed in a nickel plating bath or a tin or tin-lead alloy solder plating bath, respectively, to form a plating layer.

<Specific Configuration Example> FIG. 1 shows a configuration example of the CR composite electronic component of the present invention manufactured as described above.
In FIG. 1, the CR composite electronic component of the present invention has a dielectric layer 2, an internal electrode layer 3, a first electrode layer 4, a second electrode layer 5, and a third electrode layer 6. . Further, it is preferable that the terminal electrode constituted by the first to third electrode layers has a plating layer on the outside thereof. Further, the second electrode layer 5 has a resistance value corresponding to the minimum thickness and the conductivity regulated by the metal oxide and the like. Here, FIG. 1 shows a case where the second electrode layer 5 is formed on both terminals of the CR composite electronic component. However, the second electrode layer 5 may be formed on only one of the terminals, in which case the terminal contributing to the equivalent series resistance. Only one of the electrodes is used.

In the above description, the first electrode layer to the third electrode layer
Although the case where the electrode layer of the present embodiment exists alone has been described, for example, the structure of the first electrode layer to the third electrode layer has a double structure, or the third electrode layer is first provided at the end of the chip body. A first electrode layer to a third electrode layer may be further provided thereon, and the first to third electrodes may be provided in any of the terminal electrodes. It suffices if there is a layer portion.

[0060]

EXAMPLES Next, the present invention will be described more specifically with reference to examples.

<Example 1> Ba was used as a main material of the dielectric layer.
CO ₃ (average particle size: 2.0 μm) and TiO ₂ (average particle size: 2.0 μm) were prepared. The atomic ratio of Ba / Ti is 1.00. In addition to this, 0.2 wt% of MnCO ₃ as an additive to BaTiO ₃ , MgCO ₃
The 0.2 wt%, 2.1 wt% of _{Y 2 O 3, (BaCa)} S
2.2 wt% of iO ₃ was prepared. Each raw material powder was mixed with an underwater ball mill and dried. The obtained mixed powder was 1250
Calcination was performed at ℃ for 2 hours. This calcined product was pulverized with an underwater ball mill and dried. An acrylic resin as an organic binder and methylene chloride and acetone as organic solvents were added to the obtained calcined powder and further mixed to obtain a dielectric slurry.
The obtained dielectric slurry was used as a dielectric green sheet using a doctor blade method.

As an internal electrode material, a base metal Ni powder (average particle size: 0.8 μm) was prepared, and ethyl cellulose as an organic binder and terpineol as an organic solvent were added thereto and kneaded using a three-roll mill. This was used as an electrode paste.

As the first electrode layer paste raw material,
Cu powder of metal for electrode layer (average particle size: 0.5 μm)
And a strontium-based glass
What added wt% was prepared. To this, an acrylic resin as an organic binder and terpineol as an organic solvent were added and kneaded using a three-roll mill to obtain paste for each terminal electrode.

As a paste material for the third electrode layer, Ag
A powder (average particle size: 0.5 μm) and a powder obtained by adding 1 wt% of lead borosilicate glass to this Cu powder were prepared. To this, an acrylic resin as an organic binder and terpineol as an organic solvent were added and kneaded using a three-roll mill to obtain paste for each terminal electrode.

In order to obtain a predetermined thickness, several green sheets are laminated, and the edges of the internal electrode paste are alternately exposed from the edges of the dielectric layer paste by screen printing on the green sheets. A predetermined number of printed green sheets are laminated, and finally, a predetermined number of green sheets on which no internal electrodes are printed are laminated and thermocompression-bonded, and the shape of the chip is 3.2 × 1. 6 × 1.0mm
To obtain a green chip.

The obtained green chips are put in the air for 80 minutes.
Dry at 30 ° C. for 30 minutes. Then humidified N ₂
+ H ₂ (N ₂ 3%) in a reducing atmosphere, kept at 1300 ° C. for 3 hours, fired, and further humidified N ₂ oxygen partial pressure 10
^It was kept at 1000 ° C. for 2 hours in an atmosphere of ⁻⁷ atm to obtain a chip body.

At the both ends of the obtained chip body, the Cu
And a glass frit are added to the metal component in an amount of 7% by weight, and a paste for the first electrode layer in which these are dispersed in an organic vehicle is applied, dried, and dried at 770 ° C. in an N ₂ -H ₂ atmosphere.
And baked for 10 minutes to form a first electrode layer.

Next, the above-described Ag and glass frit were added to both ends of the chip body on which the first electrode layer was formed at 1 wt% with respect to the metal component, and these were dispersed in an organic vehicle. An electrode layer paste is applied on the first electrode layer by dipping, dried, and dried in air.
The film is held at 0 to 750 ° C. for 10 minutes and fired to form the third electrode layer and simultaneously oxidize the surface of the first electrode layer to form the second electrode layer.
Was formed. At this time, the firing temperature was set to 6
Baking is performed at each temperature of 00 ° C., 650 ° C., 700 ° C., and 750 ° C., and the holding time is 1 minute, 5 minutes, and 10 minutes.
Of the electrode layer was controlled. When the second electrode layer was analyzed by X-ray diffraction, CuO ₂ and Cu ₃ O ₄ were confirmed.

Next, a nickel plating layer and a tin-lead alloy plating layer were sequentially formed on the obtained sample of each additive composition by an electrolytic method to obtain a CR composite electronic component. The capacitance of the obtained sample was 1 μF. In addition, ESR was measured for each of the obtained samples. The results are shown in FIG. In addition, among the obtained samples, the firing temperature was 620.
FIG. 3 is a cross-sectional photograph of the terminal portion of the sample under the conditions of ° C. and a holding time of 10 minutes, and FIG. 4 is an enlarged photograph thereof.

As is clear from FIGS. 3 and 4, the second electrode layer is formed between the first electrode layer and the third electrode layer (in the form of a strip near the center of the terminal electrode). Darkened area). Further, the obtained CR composite electronic component is
When used as a power supply bypass capacitor of a C-DC converter and operated while changing the switching frequency from 1 kHz to 10 MHz, it operated normally without voltage fluctuation phenomenon such as oscillation.

As is apparent from FIG. 2, the ESR can be changed by controlling the firing temperature of the third electrode layer and the holding time thereof, and this can be controlled.

<Example 2> In Example 1, instead of Cu powder, Ni powder (average particle diameter: 0.4 μm) and Ni-Cu powder (average particle diameter: 0.1 μm) were used as the material of the first electrode layer. 5
μm), Fe powder (average particle size: 0.5 μm) and Co powder (average particle size: 0.01 to 10 μm), except that samples were obtained in the same manner as in Example 1.

The ESR of each of the obtained samples was measured in the same manner as in Example 1.
Almost the same results were obtained although there was a difference in the magnitude of SR.

Example 3 In Example 1, Au powder (average particle size: 1.0 μm) was used as the material for the third electrode layer.
), Pt powder (average particle size: 0.1 to 5 μm), Pd powder (average particle size: 0.01 to 5 μm), Rh powder (average particle size: 0.1 to 10 μm), Ir powder (average particle size) : 0.1
A sample was obtained in the same manner as in Example 1 except that を 10 μm) was used.

The ESR of the obtained sample was measured in the same manner as in Example 1.
Almost the same results were obtained although there was a difference in the magnitude of R.

<Example 4> In Example 1, as the first electrode layer paste raw material, the first electrode layer metal Ni was used.
A powder (average particle size: 0.5 μm) and a powder obtained by adding 7 wt% of strontium-based glass to this Ni powder were prepared. To this, an acrylic resin as an organic binder and terpineol as an organic solvent were added and kneaded using a three-roll mill to obtain paste for each terminal electrode.

As the third electrode layer paste raw material,
Pd powder of metal for electrode layer (average particle size: 0.5 μm)
And 1 wt% of lead borosilicate glass to this Pd powder
What was added was prepared. To this, an acrylic resin as an organic binder and terpineol as an organic solvent were added and kneaded using a three-roll mill to obtain paste for each terminal electrode.

The green chip obtained in the same manner as in Example 1 was left in air at 80 ° C. for 30 minutes and dried.
Then, it is fired at 1300 ° C. for 3 hours in a humidified N ₂ + H ₂ (N ₂ 3%) reducing atmosphere, and further fired at 1000 ° C. in a humidified N ₂ oxygen partial pressure of 10 ⁻⁷ atm.
For 2 hours to obtain a chip body.

At the both ends of the obtained chip body, the first
The electrode layer paste is applied, dried, and baked at 1000 ° C. for 10 minutes in a neutral or reducing atmosphere to obtain Ni.
A terminal electrode was obtained (first electrode layer).

Next, a third electrode layer paste is applied on the first electrode layer by dipping, and dried.
In the air, the resultant was held at 800 ° C. for 1 minute and fired to form a third electrode layer, and simultaneously oxidize the surface of the first electrode layer to form a second electrode layer. When the second electrode layer was analyzed by X-ray diffraction, NiO was confirmed.

Next, a nickel plating layer and a tin-lead alloy plating layer were sequentially formed on the obtained sample of each additive composition by an electrolytic method to obtain a CR composite electronic component. The capacitance of the obtained sample was 1 μF. When the ESR of the obtained sample was measured, it was 500 mΩ. In the third electrode paste, when the metal used was changed from Pd to Pt, almost the same results were obtained. Also, the obtained CR composite electronic component is DC-DC
When used as a power supply bypass capacitor for the converter, it operated normally without voltage fluctuation phenomena such as oscillation.

<Example 5> In Example 4, a first electrode layer paste was applied to both ends of the obtained green chip and dried. Next, a third electrode layer paste was applied on both ends of the green chip to which the first electrode layer was applied by dipping on the first electrode layer paste, and dried.

The green chip to which the terminal electrode paste was applied was dried at 80 ° C. for 30 minutes in the air.
Then, it is fired at 1300 ° C. for 3 hours in a humidified N ₂ + H ₂ (N ₂ 3%) reducing atmosphere, and further fired at 1000 ° C. in a humidified N ₂ oxygen partial pressure of 10 ⁻⁷ atm.
For 2 hours, and then in air at 700 ° C. for 10 minutes to cool to form a chip, simultaneously form the first and third electrode layers, and simultaneously oxidize the surface of the first electrode layer. Thus, a second electrode layer was formed. When the second electrode layer was analyzed by X-ray diffraction, NiO was confirmed.

Next, a nickel plating layer and a tin-lead alloy plating layer were sequentially formed on the obtained sample of each additive composition by an electrolytic method to obtain a CR composite electronic component. The capacitance of the obtained sample was 1 μF. When the ESR of each obtained sample was measured, it was found to be 200 mΩ
Met. Further, the obtained CR composite electronic component is DC-D
When used as a power supply bypass capacitor of the C converter, it operated normally without causing a voltage fluctuation phenomenon such as oscillation.

[0085]

As described above, according to the present invention, no special firing conditions are required, the manufacturing process is simple, the production cost is low, and a CR or (L / C) R series circuit can be easily obtained. In addition, it is possible to provide a CR composite electronic component whose resistance value is easily controlled and a method of manufacturing the same.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a basic configuration of a CR composite electronic component of the present invention.

FIG. 2 is a graph showing an ESR of a CR composite electronic component sample of the present invention.

FIG. 3 is a drawing-substituting photograph of a cross section of a terminal electrode portion of the CR composite electronic component of the present invention.

FIG. 4 is an enlarged photograph of FIG. 3;

[Explanation of symbols]

 2 Dielectric layer 3 Internal electrode 4 First electrode layer (terminal electrode) 5 Second electrode layer (terminal electrode) 6 Third electrode layer (terminal electrode)

Continuation of the front page (72) Inventor Yasunori Tokuoka 1-1-13 Nihonbashi, Chuo-ku, Tokyo Inside TDK Corporation

Claims (12)

[Claims] 1. A dielectric layer and an internal electrode are alternately laminated, and the internal electrode and a terminal electrode formed at an end of the CR composite electronic component are electrically connected to form a capacitor. , At least one of the terminal electrodes is first to first from the internal electrode side.
A first electrode layer containing one or more of Fe, Co, Cu and Ni; and a second electrode layer comprising an oxide of the first electrode layer. A CR composite electronic component, wherein the third electrode layer contains one or more of Ag, Au, Pt, Pd, Rh, Ir, and Ru. 2. The method according to claim 1, wherein the second electrode layer comprises Fe as an oxide.
O, α-Fe ₂ O ₃ , γ-Fe ₂ O ₃ , Fe ₃ O ₄ , Co
O, Co ₃ O ₄ , Cu ₂ O, Cu ₃ O ₄ , CuO, NiO
2. The CR composite electronic component according to claim 1, comprising one or more of the following. 3. The first electrode layer is made of Ag, Au, P
3. The CR composite electronic component according to claim 1, wherein one or more of t, Pd, Rh, Ir, and Ru are contained in an amount of 10 wt% or less. 4. The method according to claim 1, wherein the first to third electrode layers are made of glass.
The CR composite electronic component according to any one of claims 1 to 3, which contains -20 wt%. 5. The CR composite electronic component according to claim 1, wherein the equivalent circuit has a CR or (LC) R series circuit. 6. The CR composite electronic component according to claim 1, wherein said internal electrode layer contains Ni. 7. The CR composite electronic component according to claim 1, further comprising a plating layer outside said terminal electrode. 8. A green chip is formed by alternately laminating a dielectric layer and an internal electrode layer, and is baked into a chip body. A first electrode layer paste is applied to the chip body. Firing in a neutral or reducing atmosphere to form precursors for the first and second electrode layers, further applying a third electrode layer paste, and firing in an oxidizing atmosphere , The first and second
9. A CR composite electronic device which oxidizes the vicinity of the interface between the precursor of the electrode layer and the third electrode layer to form the first to third electrode layers to obtain the CR composite component according to claim 1. The method of manufacturing the part. 9. The first electrode layer paste or the second electrode layer paste
9. The CR composite electronic component according to claim 8, wherein the electrode layer paste has metal particles having an average particle size of 0.1 to 10 [mu] m. 10. A green chip is formed by alternately laminating a dielectric layer and an internal electrode layer, and is baked into a chip body. A paste for a first electrode layer is applied to the chip body, Further, a third electrode layer paste is applied thereon and fired in a neutral or reducing atmosphere. During the cooling process, the third electrode layer paste is turned into an oxidizing atmosphere to form a third electrode layer paste fired body. 8. A method for manufacturing a CR composite electronic component according to claim 1, wherein the vicinity of the interface with the electrode layer is oxidized to form the first, second, and third electrode layers to obtain the CR composite component according to claim 1. 11. A green chip is formed by alternately laminating dielectric layers and internal electrode layers, a first electrode layer paste is applied to the green chip, and a third electrode layer is further formed thereon. The paste for application is baked in a reducing atmosphere, and the vicinity of the interface with the third electrode layer of the first electrode layer paste baked body is oxidized in an oxidizing atmosphere during a cooling process, thereby forming the green chip. A method of manufacturing a CR composite electronic component according to claim 1, wherein the first, second, and third electrode layers are formed to obtain the CR composite component according to claim 1. 12. The CR composite electronic device according to claim 10, wherein the first electrode layer contains Ni, and the third electrode layer contains one or more of Pd, Pt, Rh, Ir, and Ru. The method of manufacturing the part.