JPH05121239A - Inductance part and its manufacture - Google Patents

Abstract

PURPOSE:To miniaturize and thin it by having a coil, where insulating layers and conductor parts are stacked alternately, on a ceramic substrate, and having a magnetic body, which is in contact with the ceramic substrate or spaced apart from it by a necessary distance. CONSTITUTION:This inductance part has a coil, where insulating layers 4 and conductor parts 5 are stacked alternately, on a ceramic substrate 1, and further, has a magnetic substance 2, which is in contact with the ceramic substrate 1 or required space apart from it, or a pair of magnetic substances 2 which are in contact with the ceramic substrate 1 through through holes or required space apart. And, as the ceramic substrate 1, a ceramic substrate of alumina, mullite, beryllia, steatite, or the like is used. Moreover, as the magnetic substance 2, ferrite magnetic substance, permalloy, Sendust, or the like is used. Hereby, a great part of the magnetic circuit is constituted of the magnetic substance excellent in soft magnetic property, it becomes possible to made it into a thin or small inductance part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inductance component having a magnetic material, and more particularly to a thin inductance component having excellent characteristics and a manufacturing method thereof.

[0002]

2. Description of the Related Art Inductance parts are widely used as coils, transformers, etc. for various communication devices, consumer devices, etc., and in recent years, small or thin inductance parts are increasingly required.

As a small-sized inductance component, a laminated inductor in which magnetic layers and conductors are alternately laminated (for example, JP-A-55-91103) and a laminated transformer having a similar structure have been proposed. The present situation is to use a limited ferrite magnetic material that can be sintered at a low temperature, for example, a NiZnCu-based ferrite because it is obtained by simultaneously firing a conductor, that is, a ferrite magnetic material and a conductor. Other ferrite magnetic materials having excellent magnetic characteristics such as magnetic permeability or magnetic flux density for downsizing, such as Mn
Zn-based ferrite cannot be used. On the other hand, for an inductance component obtained by winding a ferrite magnetic material sintered under sufficient conditions, a ferrite magnetic material is used by firing alone. Therefore, various types of ferrite magnetic materials can be used, and the excellent magnetic characteristics of the ferrite magnetic material can be utilized. But,
There is a limit to downsizing, especially thinning, and in general, a coated copper wire is used for the winding, and therefore there is also a limit to heat resistance.

[0004]

As described above, various inductance components have been proposed so far.
It is used by making full use of the characteristics of various types of ferrite magnetic materials, and is compact or thin. Furthermore, miniaturization of various modules using inductance components, high integration, or mounting of wiring board and inductance components. However, there is a problem in that an inductance component that satisfies the manufacturing process for simultaneously performing the above is not obtained.

The present invention solves the above-mentioned problems of the prior art by satisfying a thin or small size while exhibiting sufficient magnetic properties of various types of ferrite magnetic materials, and various modules using inductance components. It is an object of the present invention to provide an inductance component that satisfies such requirements as miniaturization and high integration.

[0006]

In order to solve the above-mentioned problems, the present invention has a coil in which insulating layers and conductor portions are alternately laminated on a ceramic substrate, and further, the coil is in contact with or required to the ceramic substrate. This is an inductance component having a pair of magnetic bodies that are separated from each other by a gap or a gap between a magnetic body or a through hole of a ceramic substrate.

[0007]

By using the above-described inductance component, that is, it has a coil composed of ceramics and the like, which are obtained by alternately laminating insulating layers and conductors on a ceramic substrate, and has a gap that is in contact with or required by the ceramic substrate. The magnetic circuit is composed mostly of magnetic material by making it an inductance component that has a pair of magnetic materials that are in contact with each other through a through hole of a ceramic substrate or through a through hole of a ceramic substrate or a required gap. The soft magnetic characteristics can be sufficiently exhibited. For example, if the magnetic material is ferrite, the magnetic characteristics of various types of ferrite magnetic materials can be sufficiently exhibited. Moreover, since it is a coil in which insulating layers and conductors are alternately laminated, it is a thin or small inductance component. Furthermore, since it is an inductance component made of a material having sufficient heat resistance, heat resistance and reliability can be ensured, and an inductance component that enables a manufacturing process, etc., in which the wiring board and the inductance component are mounted at the same time. Become.

[0008]

EXAMPLE An example of the present invention will be described below.

The inductance component of the present invention has a coil in which insulating layers and conductor portions are alternately laminated on a ceramic substrate (in some cases, a ferrite magnetic layer is provided between the ceramic substrate and the coil), and further, the ceramic. It is an inductance component having a magnetic body that is in contact with a substrate (or a ferrite magnetic layer in some cases) or has a gap therebetween, or a pair of magnetic substances that are in contact with each other through a through hole of a ceramic substrate or have a gap therebetween. Thus, the inductance component of the present invention can be roughly divided into three. One is composed of three parts of a ceramic substrate, a magnetic material and a coil, and the coil is further composed of at least two parts of an insulating layer and a conductor part. The second is composed of a ceramic substrate, a pair of magnetic materials and a coil, and the third is an inductance component composed of a ceramic substrate, a ferrite magnetic layer, a coil and a magnetic material.

The ceramic substrate is a general ceramic substrate, and the most frequently used one is an alumina substrate. It may be advantageous to use a magnetic substrate such as a ferrite substrate rather than a non-magnetic substrate such as an alumina substrate. This is effective because the ferrite substrate constitutes a part of the magnetic circuit and thus the inductance component is made thinner, and the inductance is improved and the magnetic shield property is also improved. The magnetic material means a magnetic material having excellent soft magnetic characteristics, and particularly, an oxide magnetic material and a ferrite sintered material have good compatibility with the inductance component of the present invention. The insulating layer forming the coil includes glass having electric insulation, glass containing oxides or raw materials for various ceramic substrates, and the like, and any material having high electric insulation may be used. The conductor material is a material having excellent conductivity. As described in detail in the manufacturing method of the present invention, the ferrite magnetic layer is a layer in which ferrite powders are bonded to each other or bonded to each other with a substance having a low melting point, which is different from the above-mentioned magnetic material, and has relatively many holes. It is the existing layer. For example,
When the above-mentioned magnetic material is a ferrite sintered body, the difference from this ferrite magnetic layer is that the ferrite sintered body is composed of various types of spinel type ferrite that are generally known to exclude a small amount of additives. The density is very high with few holes. On the other hand, the ferrite magnetic layer is similar to the above-described ferrite layer of the laminated inductor or the like, and is a layer containing a binder having a low melting point such as glass in the case of ferrite having many holes and a high sintering temperature.

As a manufacturing method, a method is obtained in which insulating layers and conductor portions are alternately laminated on a ceramic substrate to form a coil, and a magnetic material is fixed on the ceramic substrate before or after the coil is fired. Forming a coil on the magnetic body,
A method of fixing a magnetic body and a ceramic substrate before or after firing the coil, forming a coil on the ceramic substrate, and forming a pair of magnetic bodies through the through holes of the ceramic substrate before or after firing the coil. Method obtained by fixing, method obtained by forming a coil on one magnetic body of a pair of magnetic bodies, and fixing with another magnetic body through a through hole of the ceramic substrate before or after firing the coil, or a ceramic substrate There is a method in which a ferrite magnetic layer is formed on the ferrite magnetic layer, a coil is further formed on the ferrite magnetic layer, and a magnetic material is fixed to the ferrite magnetic layer before or after firing of the ferrite magnetic layer and the coil.

There is a method such as a printing method, a depping method or a spin coating method for forming the conductor portion or the insulating layer which constitutes the coil, and it is also possible to use a laser or the like for forming the conductor pattern. That is, it is a method of forming a coil by forming a conductor layer on the entire surface and then removing a part of the conductor layer with a laser. The ferrite magnetic layer is similarly formed by a method such as printing. These may be a method of directly forming each layer on a generally known ceramic substrate or a magnetic material, or a method of laminating each layer in the form of a green sheet. Furthermore, there is also a method in which a mica or a very thin insulator plate is used as an insulating layer and a conductor pattern is formed on the mica or the insulating plate by printing or the like to produce a coil.

A specific example of the inductance component of the present invention will be described in more detail with reference to the drawings. 1 (a), 1 (b) and 2
3 (a) and 3 (b) and FIGS. 3 (a) and 3 (b) show an exploded perspective view of a typical inductance component of the present invention and a schematic view of a cross section of a coil portion. 1, 2 and 3 are the three typical types of inductance components of the present invention described above. 1, 2 and 3, 1 is a ceramic substrate, 2 is an E-type or EI-type magnetic body, and 3 is a ferrite magnetic layer. Reference numeral 4 is an insulating layer, and 5 is a conductor portion. The insulating layer 4 and the conductor portion 5 form a coil. The conductor portion 5 may be composed of any number of layers.

The ceramic substrate 1 is a generally known ceramic substrate, and includes various ceramic substrates such as alumina, mullite, beryllia, steatite, forsterite, magnesia, titania, and ferrite.

The magnetic material 2 includes ferrite magnetic material, permalloy, sendust, and other oxide-based or metal-based magnetic materials having excellent soft magnetic characteristics.

The ferrite magnetic layer 3 includes various spinel-type ferrites or mixtures other than MnZn-based ferrite, NiZn-based ferrite, and NiZnCu-based ferrite, and one of the magnetic materials 2 is a ferrite magnetic material. Since the conditions are significantly different, there are differences in structure or magnetic properties.

As the material for forming the insulating layer 4, various kinds of ceramics or various kinds of glass ceramics, nitrides, carbides, Ni, as in the above-mentioned ceramics substrate 1, are used.
Examples include Zn-based ferrite, NiZnCu-based ferrite, and mica. Although referred to as an insulating layer in the present invention, the material for forming the insulating layer 4 may be a material called a dielectric material or a non-magnetic material other than an insulating material, as long as it is a material having a high electric resistance. Examples of the dielectric include those contained in the above-mentioned insulator, barium titanate, potassium niobate, and the like. Examples of non-magnetic materials include zinc ferrite and iron oxide, which are compatible with spinel ferrite.

As the material for the conductor portion 5, there are metals such as silver, copper, gold, silver-palladium, silver-platinum alloy, etc., which are often used in the ordinary printing method for forming a conductor. The resistance and melting point of the conductor are important conditions for selection.

As described above, the ceramic substrate 1, the magnetic body 2, the ferrite magnetic layer 3, the insulating layer 4 and the conductor portion 5 do not necessarily have to be made of one substance, and may be made of a mixture of various substances. Good. In this way, by using an inductance component including the ceramic substrate 1, the magnetic body 2, the ferrite magnetic layer 3, and the coil (composed of the insulating layer 4 and the conductor portion 5), a thin or compact ferrite sintered body having sufficient characteristics can be obtained. It is possible to obtain a small inductance component. Since all or most of the magnetic circuit is composed of a ferrite sintered body, it is an inductance component that is thin or small but exhibits excellent electrical characteristics. When one electric module, for example, a DC-DC converter is manufactured using a ceramic substrate, and when a thick film resistor or a capacitor is used, the characteristics of the inductance component of the present invention can be further exerted. It is possible to obtain a manufacturing process in which the wiring board and the inductance component of the present invention are collectively mounted, or high-density mounting, and high reliability.

The coil shape is typically a solenoid type or a plane coil such as a spiral coil having many turns on the same surface. The solenoid type is effective for miniaturization and the spiral type is effective for thinness. Is.

Ferrite magnetic layer 3, insulating layer 4 and conductor portion 5
The paste for forming is a powder and a solvent such as butyl carbitol, terpineol, alcohol, a binder such as ethyl cellulose, polyvinyl butyral, polyvinyl alcohol, polyethylene oxide, ethylene-vinyl acetate, and various oxides or glass. Butyl benzyl phthalate,
A plasticizer such as dibutyl phthalate or glycerin or a dispersant may be added. Each layer is formed using a kneaded product obtained by mixing these. An inductance component is obtained by firing a laminate of these in a predetermined structure as described above at a predetermined temperature.

The firing temperature range is from about 700 ° C. to 13
It is in the range of 00 ° C. In particular, it depends on the constituent material of the conductor that forms the coil. For example, if silver is used as the conductor material, it is necessary to keep the temperature relatively low, and with an alloy of silver and palladium, it is possible even at a relatively high temperature.

Next, more specific examples of the present invention will be described. (Example 1) 20 g of glass powder having a firing temperature of 850 ° C
On the other hand, 6 g of a mixture of terpineol and ethyl cellulose in a weight ratio of 100: 6 (hereinafter abbreviated as binder) was added and mixed, and then kneaded using a three-roll to prepare a glass paste. 30 more silver powder
A silver paste was similarly prepared by using g and 3 g of a binder. Using these pastes, the substrate insulating pattern shown in FIG. 4 (a) was formed into a glass paste by screen printing on a MnZn ferrite substrate, a NiZn ferrite substrate and a 96% alumina substrate each having a length of 50 mm and a width of 1 mm. Was printed using. Next, the coil A pattern shown in FIG. 4B was printed using silver paste, and the insulating pattern shown in FIG. 4C was printed thereon using glass paste. Further, the coil B shown in FIG.
The pattern was printed with silver paste, and the inter-coil insulation pattern shown in FIG. 4 (e) was sequentially printed with glass paste to form a coil. Drying after printing was performed at 150 ° C., and each layer was printed twice to form a coil. The plate used for printing is made of stainless steel and has a size of 200 mesh. The coil is the coil A pattern shown in FIG. 4 (b) and FIG. 4 (d).
It is composed of two layers of the coil B pattern shown in FIG. Figure 4 on the coil A pattern
When the insulating pattern shown in (c) is printed, the central part of the coil A pattern (the part where the line is thickened) is exposed, and when the coil B pattern is printed on it, the two are connected at the exposed part. .

Next, the MnZn-based ferrite E-type core (E
The die core has a foot length of 0.2 mm and the core has a back thickness of 1 mm. ) Is coated with a lath paste on the contact portion with the substrate, the ferrite E-type core is brought into contact with the substrate through the glass, and the ferrite substrate and the alumina substrate are held in the atmosphere at 850 ° C. for 10 minutes, Firing was performed under the condition of cooling in nitrogen.

Next, the inductance of the inductor obtained by firing was measured. The measurement was performed using an LCR meter, and the measurement frequency was 500 kHz. 200 μH for MnZn-based ferrite substrate, 150 μH for NiZn-based ferrite substrate, and 50 μH for alumina substrate.
Met.

As described above, the inductor of the present invention is an inductance component exhibiting excellent electrical characteristics. Moreover, although it uses an E-shaped core of a ferrite sintered body, it is thin and has a high heat resistance because it is manufactured by a thick film process. It was an inductance component that was rich and fully exhibited the magnetic characteristics of a sintered ferrite magnetic material.

Example 2 A glass paste was prepared by mixing 6 g of a binder with 20 g of glass powder having a firing temperature of 950 ° C., and then kneading the mixture. Using the same three types of substrates as in Example 1, the substrate insulation, the coil A pattern, the insulation pattern, the coil B pattern, and the inter-coil insulation pattern were printed in the same manner as in Example 1. The same silver paste as in Example 1 was used. Further coil A
Using the same coil pattern (C to H) different in coil terminal position from the pattern or coil B, the above-described printing (coil A pattern, insulation pattern, coil B pattern and inter-coil insulation) is repeated, that is, coil A In addition to the coil B and 6 types of C to H coil patterns, 5 coils were laminated as shown in FIG.
FIG. 5 is a diagram schematically showing a cross section of the coil portion, where A to H show that the lead wire of the coil and the terminal position are different, and 11 to 14 show the coil number. Coil 12 is 2
Since the terminal positions are the same, two coils are connected in parallel to form one coil. One coil is formed by A and B, and one coil is formed by C and D in the same manner. is doing.

Next, a glass paste is applied to the contact portion of the E-type core of MnZn-based ferrite (the length of the E-type core is 0.6 mm and the thickness of the core is 1 mm) with the substrate. After coating, the E-type core was brought into contact with the substrate through the glass, and the ferrite substrate and the alumina substrate were held in the atmosphere at 850 ° C. for 10 minutes, and then fired under the condition of cooling in nitrogen. In this way, the glass paste was applied between the substrate and the E-type core to fix them and form a gap.

Inductance components containing four coils obtained by firing, that is, the inductance of a transformer, were similarly measured. The inductance of the coil 12 is MnZ
In the case of n-type ferrite substrate, it is 200 μH.
The value was 150 μH for the n-type ferrite substrate and 50 μH for the alumina substrate.

Further, when the coil 11 other than the coil 12, the coil 13 or the coil 14 is opened or shorted respectively and the coupling state of the coils is obtained as a coupling coefficient, both are 0.998 when the coil 11 or the coil 14 is shorted. And 0.999 when the coil 13 was short-circuited. As described above, the inductance component of the present invention showed excellent characteristics as a transformer with little leakage flux.

(Embodiment 3) Thickness is 0.02 to 0.03
Using a plurality of mm mica plates, the coil A pattern and the coil B shown in FIG.
Printing was performed using the silver paste prepared in. An insertion hole for an E-shaped core was formed in this mica plate using a carbon dioxide laser. The mica on which the coil A pattern and the coil B were formed was overlapped and connected at the center with silver paste.

Next, mica and MnZn ferrite E-type cores were fixed to the same three types of substrates as in Example 1 using a glass paste, and these were heated at 850 ° C. for 2 hours in air.
After holding for 0 minutes, firing was performed under the condition of cooling in nitrogen.

When the inductance was measured in the same manner as above, it was 200 μm for the MnZn ferrite substrate.
H, 150 μH for the NiZn-based ferrite substrate, and 50 μH for the alumina substrate.

Example 4 20 g of glass powder having a firing temperature of 880 ° C. was added with 6 g of a binder and mixed, and then kneaded to prepare a glass paste. Using the same three types of substrates as in Example 1, the entire surface pattern shown in FIG. 6 was printed on each substrate using glass paste. Next, as in Example 1, the coil A pattern, the insulation pattern, the coil B pattern, and the inter-coil insulation were printed in order. The same silver paste as in Example 1 was used. Further, similar to the second embodiment, the same coil pattern (C to H) in which the coil terminal position is different from the coil pattern A or the coil B is used, and the above-mentioned printing (coil A pattern, insulation pattern, coil B pattern and coil) is performed. Insulation) was repeated, that is, five types of C to H coil patterns were used in addition to the coils A and B, and five coils were laminated as shown in FIG.

Next, an MnZn ferrite E-type core (E-type core has a leg length of 0.6 mm and a core spine thickness of 1 mm) is inserted into the core insertion hole, 850 ferrite substrate and alumina substrate in air
After holding at 0 ° C. for 10 minutes, firing was performed under the condition of cooling in nitrogen. In this way, the E-shaped core and the substrate were fixed and the gap was formed by first printing the entire surface pattern shown in FIG. 6 on the substrate.

The inductance was measured as before. The inductance of the coil 12 was 200 μH for the MnZn-based ferrite substrate, 150 μH for the NiZn-based ferrite substrate, and 50 μH for the alumina substrate, which were characteristics similar to those of Example 2.

Further, when the coil 11 other than the coil 12, the coil 13 or the coil 14 is opened or short-circuited to determine the coupling state of the coils as a coupling coefficient, both are 0.998 when the coil 11 or the coil 14 is short-circuited. And 0.999 when the coil 13 was short-circuited. As described above, the inductance component of the present invention showed excellent characteristics as a transformer with little leakage flux.

(Embodiment 5) A ferrite E-shaped core as shown in FIG.
A 96% alumina substrate having a thickness of 0 mm and a thickness of 0.635 mm was used to form a coil on the alumina substrate by the same method and using the same paste as in Example 1.

Next, an E-type core of MnZn-based ferrite (E-type core has a foot length of 0.8 mm and a core spine thickness of 1 mm) and an I-type core having a thickness of 1 mm are used. Glass paste is applied to the contact portion, and a ferrite E-type core and an I-type core are brought into contact with each other by passing the legs through the insertion holes of the alumina substrate, and the ferrite core and the alumina substrate are held in the atmosphere at 850 ° C. for 10 minutes, then nitrogen is applied. It was fired under the condition of cooling in it.

When the inductance was measured in the same manner as before, it was 200 μH. Unlike the first embodiment, the inductor of the present embodiment uses a commonly used alumina substrate and exhibits extremely excellent inductance.

A transformer was prototyped using the same alumina substrate as in Example 2, but the same characteristics as those obtained when using the ferrite substrate were obtained.

Example 6 20 g of NiZnCu type ferrite powder and 7 g of binder were mixed and kneaded, and N
An iZnCu-based ferrite paste was prepared.

An alumina substrate of 50 mm in length and width and 1 mm in thickness was formed on the whole surface pattern shown in FIG. 6 by using NiZnCu type ferrite paste to have a thickness of 0.5 in a dry state.
First printed until it became mm. Next, the glass paste and the silver paste produced in Example 1 were used to form a coil in the same manner as in Example 1. Printing was performed according to the procedure shown in Example 1.

Next, after holding in the air at 850 ° C. for 10 minutes, firing was performed under the condition of cooling in a nitrogen atmosphere.

When the inductance was measured in the same manner as above, it was 80 μH.

[0046]

According to the present invention, a coil having an insulating layer and a conductor portion alternately laminated on a ceramic substrate is provided, and a magnetic body or a through hole of the ceramic substrate which is in contact with the ceramic substrate or has a necessary gap. Sintering of various systems that make up the majority of the magnetic circuit by using an inductance component that has a pair of magnetic bodies that are in contact with each other or that have a required gap between them, and that exerts sufficient magnetic characteristics as a magnetic body. Ferrite magnetic material can be used,
The inductance component has extremely excellent characteristics.
Furthermore, since the coil is a thick film coil in which insulating layers and conductor layers are alternately laminated, the height of the coil is thin, which makes the inductance component extremely thin or small. Further, the present invention provides an excellent inductance component having both sufficient heat resistance and high reliability.

[Brief description of drawings]

1A and 1B are exploded perspective views and cross-sectional views of a coil portion showing a configuration of a typical inductance component of the present invention.

2 (a) and 2 (b) are exploded perspective views showing a configuration of a typical inductance component of the present invention and a sectional view of a coil portion.

3 (a) and 3 (b) are exploded perspective views showing a configuration of a typical inductance component of the present invention and a sectional view of a coil portion.

FIG. 4 is a diagram showing each pattern for forming a coil in Examples (a) to (e).

FIG. 5 is a schematic cross-sectional view showing a laminated state of coils in an example.

FIG. 6 is a diagram showing an entire surface pattern in an example.

[Explanation of symbols]

 1 Ceramic Substrate 2 Magnetic Material 3 Ferrite Magnetic Layer 4 Insulating Layer 5 Conductor

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Internal reference number for FI Technical indication H01F 41/04 D 8019-5E (72) Inventor Hiroyuki Handa 1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric Sangyo Co., Ltd.

Claims (6)

[Claims] 1. An inductance component having a coil formed by alternately laminating insulating layers and conductors on a ceramic substrate, and further having a magnetic body that is in contact with the ceramic substrate or has a required gap. 2. An inductance component having a coil formed by alternately laminating insulating layers and conductors on a ceramic substrate, and further having a pair of magnetic bodies that are in contact with each other through a through hole of the ceramic substrate or have a required gap. 3. A magnetic field comprising a ferrite magnetic layer on a ceramic substrate, and a coil formed by alternately laminating an insulating layer and a conductor portion on the ferrite magnetic layer, the magnetic layer being in contact with the ferrite magnetic layer or having a required gap. Inductance component having a body. 4. A method of manufacturing an inductance component obtained by forming a coil with an insulating layer and a conductor portion on a ceramic substrate, and fixing a magnetic material on the ceramic substrate before or after firing of the coil. 5. A method of manufacturing an inductance component obtained by forming a coil with an insulating layer and a conductor portion on a ceramic substrate and fixing a pair of magnetic bodies through the through holes of the ceramic substrate before or after firing of the coil. 6. A ferrite magnetic layer is formed on a ceramic substrate, and a coil is formed by alternately laminating an insulating layer and a conductor portion on the ferrite magnetic layer, and before or after firing the ferrite magnetic layer and the coil. A method of manufacturing an inductance component obtained by fixing the body on a ferrite magnetic layer.