JP2001118728A - Multilayer inductor array - Google Patents

Abstract

(57) [Problem] To provide a multilayer inductor array having a stable inductance value, capable of further miniaturizing a product, preventing restrictions on component arrangement, and reducing a mounting area. SOLUTION: Internal conductors each having an inductor dimension corresponding to a required mounting area are provided in a plurality of specific regions juxtaposed so as to have a low magnetic coupling factor within the component dimension. 13a, 13b, 13c, 1
3d and a plurality of first insulating layers 11 formed on the upper and lower surfaces of the first insulating layer 11 for sandwiching a plurality of inductor elements provided on the first insulating layer 11. , And a plurality of inductor elements disposed on the first insulating layer 11 sandwiched between the second insulating layer 14 and the third insulating layer 15. They are stacked with a magnetic coupling factor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer inductor array which is used in various electronic equipment and has a high inductance value when a high-frequency current as noise is applied to prevent the noise from entering the electronic equipment. It is about.

[0002]

2. Description of the Related Art There has been a remarkable reduction in size and performance of electronic devices such as personal computers and mobile phones. In accordance with these trends, high-density mounting of electronic circuit parts has been attempted, and downsizing and high performance of chip components have been demanded. On the other hand, for multilayer inductors that are used several to several dozens adjacent to the bus line around the LCD display etc., the mounting area of an array in which multiple components are packaged in one package is smaller than downsizing of individual components alone. However, its usefulness is high in terms of mounting efficiency.

Hereinafter, a conventional laminated inductor array will be described.

FIG. 10 is a perspective view of a conventional laminated inductor array, and FIG. 11 is an exploded perspective view of the laminated inductor array.

In FIGS. 10 and 11, reference numeral 1 denotes a first insulating layer having a through hole 2 filled with a conductive material such as Ag and made of ferrite. Reference numeral 3 denotes a plurality of spirally formed internal conductors, which are provided on the upper and lower surfaces of the first insulating layer 1,
The tip extends to one edge of the first insulating layer 1. At this time, a plurality of independent spiral coils are formed by connecting the internal conductors 3 located on the upper and lower surfaces of the first insulating layer 1 via the through holes 2. Reference numeral 4 denotes a second insulating layer, which is provided above and below a plurality of independent spiral coils. 5 is a sintered body, the first
The insulating layer 1, the second insulating layer 4, and the internal conductor 3 are laminated and sintered. Reference numerals 6 denote external electrodes, which are formed on a plurality of opposite side surfaces of the sintered body 5 and are connected to electronic components at both ends of the independent spiral coil so as not to short-circuit the independent spiral coils. I have.

A method of manufacturing the conventional laminated inductor array having the above-described configuration will be described below with reference to the drawings.

FIGS. 12A to 12E are process diagrams showing a conventional method for manufacturing a laminated inductor array.

First, as shown in FIG. 12A, a first insulating layer 1 is formed from a ferrite powder as an inorganic material and a slurry containing a resin as a main component by a doctor blade method.
The second insulating layer 4 is formed.

Next, as shown in FIG. 12 (b), a plurality of through holes 2 are formed by punching a hole in the center of the first insulating layer 1, and a conductive material such as Ag is formed in the through holes 2. Fill the material.

Next, as shown in FIG. 12C, a plurality of spiral inner conductors 3 are formed by printing of an Ag paste or Ag plating. And the first insulating layer 1
A plurality of independent spiral coils are formed by overlapping a plurality of internal conductors 3 on the upper and lower surfaces so as to be connected via the through holes 2. Further, the tips of the plurality of internal conductors 3 are formed to extend to one edge of the first insulating layer 1. Further, a second insulating layer 4 is laminated on and under a plurality of independent spiral coils until a predetermined thickness is obtained.

Next, as shown in FIG. 12D, the laminated product is heated in air to burn and remove the resin.
The sintered body 5 is formed by sintering at a high temperature of about 50 to 950 ° C. At this time, a plurality of internal conductors 3
The tip of is exposed.

The first insulating layer 1 and the second insulating layer 4 before sintering have the same value of magnetic permeability after sintering by using the same material and the same method. .

[0013] Finally, as shown in FIG. 12 (e), the tips of the plurality of internal conductors 3 exposed from one end face of the sintered body 5 are electrically connected to both opposing side surfaces of the sintered body 5. An Ag-based conductive paste is applied so as to be connected, and 550 to 900
A plurality of external electrodes 6 were formed by baking at a temperature of ° C. to manufacture a conventional multilayer inductor array. At this time, the external electrode 6 is electrically connected to both ends of the independent spiral coil so that the independent spiral coil does not short-circuit the independent spiral coils.

[0014]

However, in the above-mentioned conventional laminated inductor array, when the distance between adjacent internal conductors 3 becomes short due to the miniaturization of components, magnetic and electrostatic between adjacent internal conductors 3 become small. Since crosstalk occurs due to the coupling, there is a problem that the inductance value of each internal conductor 3 in one laminated inductor array is not stable.

If the inductance value of the multilayer inductor array is not stable as described above, there is a risk that noise may enter the electronic device and cause the electronic device to malfunction.

As a countermeasure against this crosstalk, Japanese Utility Model 7
Structures described in microfilms and the like in JP-A-10927 and JP-A-7-10914 have been considered. In these, a common ground electrode for releasing crosstalk generated between the element bodies is formed between the element bodies, and this common ground electrode is connected to external ground electrodes at both ends in the longitudinal direction of the element body. An external ground electrode is structured to be soldered to a printed circuit board. That is, crosstalk generated between the element bodies is reduced by interposing the common ground electrode between the element bodies. However, in this structure, it is necessary to form a ground electrode on a printed circuit board which is a component mounting surface, and it is difficult to reduce the mounting area due to restrictions on the component arrangement.

The present invention solves the above-mentioned conventional problems, in which the inductance value is stabilized, and the product can be downsized.
It is an object of the present invention to provide a multilayer inductor array capable of preventing restrictions on component arrangement and reducing a mounting area.

[0018]

In order to achieve the above object, a laminated inductor array according to the present invention has a component external dimension corresponding to a required mounting area, and a low magnetic coupling factor is included in the component external dimension. In order to sandwich a plurality of first insulating layers each having an internal conductor serving as an inductor element in a plurality of specific regions arranged side by side and a plurality of inductor elements provided in the first insulating layer, A second insulating layer disposed on the upper and lower surfaces of the first insulating layer; and a third insulating layer, wherein the first insulating layer is sandwiched between the second insulating layer and the third insulating layer. A plurality of inductor elements arranged in a layer are stacked with a low magnetic coupling factor. According to this configuration, the inductance value is stable, furthermore, the size of the product is reduced, the arrangement of components is prevented, and the mounting area is reduced. Can be laminated Ndakutaarei is obtained.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention has a component external dimension corresponding to a required mounting area, and is juxtaposed to have a low magnetic coupling factor in the component external dimension. A plurality of first insulating layers each having an internal conductor that is an inductor element formed in each of the plurality of specified regions, and the first insulating layer sandwiching the plurality of inductor elements provided in the first insulating layer. A second insulating layer disposed on the upper and lower surfaces of the layer and a third insulating layer, the first insulating layer being sandwiched between the second insulating layer and the third insulating layer; According to this configuration, a plurality of inductor elements are stacked with a low magnetic coupling factor. According to this configuration, crosstalk between a plurality of internal conductors in one first insulating layer, a plurality of stacked first insulating layers, Reduce crosstalk between the formed internal conductors. Since it respectively suppressed, it is possible to stabilize an inductance value. In addition to this,
Since the crosstalk can be suppressed, a common ground electrode is not required, which has an effect that the product can be reduced in size, restrictions on component arrangement can be prevented, and a mounting area can be reduced.

According to a second aspect of the present invention, at least one fourth layer having a lower magnetic permeability than the first insulating layer, the second insulating layer, and the third insulating layer is provided between the plurality of second insulating layers. According to this configuration, the first insulating layer and the second insulating layer are provided between the internal conductors formed on the laminated first insulating layer.
Since the first and second insulating layers have a lower magnetic permeability than the third and fourth insulating layers, crosstalk between these internal conductors can be further suppressed, and the inductance value can be further stabilized. In addition, since the crosstalk can be suppressed, a common ground electrode is not required, which has an effect that the product can be reduced in size, restrictions on component arrangement can be prevented, and a mounting area can be reduced.

According to a third aspect of the present invention, the density of the fourth insulating layer after sintering is smaller than the densities of the first insulating layer, the second insulating layer, and the third insulating layer after sintering. According to this configuration, the permeability between the inner conductors formed in the stacked first insulating layers is higher than that of the first, second, and third insulating layers. Because there is a fourth insulating layer with low
Crosstalk between these internal conductors can be suppressed, thereby stabilizing the inductance value. In addition, since the crosstalk can be suppressed, a common ground electrode is not required, which has an effect that the product can be reduced in size, restrictions on component arrangement can be prevented, and a mounting area can be reduced.

According to a fourth aspect of the present invention, the compounding ratio of the plurality of oxides in the inorganic material constituting the fourth insulating layer is set to the first ratio.
According to this configuration, the mixing ratio of the plurality of oxides in the inorganic material constituting the insulating layer, the second insulating layer, and the third insulating layer is different from that of the first insulating layer. A first insulating layer, a second insulating layer, between internal conductors formed in the layers;
Since there is the fourth insulating layer having a lower magnetic permeability than the third insulating layer, crosstalk between these internal conductors can be suppressed, and thereby the inductance value can be stabilized. In addition, the ability to suppress crosstalk eliminates the need for a common ground electrode,
This has the effect of enabling downsizing of products, prevention of restrictions on component arrangement, and reduction of mounting area.

According to a fifth aspect of the present invention, a void is provided in the fourth insulating layer.
Since the first insulating layer, the second insulating layer, and the fourth insulating layer having a lower magnetic permeability than the third insulating layer exist between the inner conductors formed in the stacked first insulating layers, Crosstalk between the internal conductors can be suppressed, thereby stabilizing the inductance value. In addition, since the crosstalk can be suppressed, a common ground electrode becomes unnecessary, so that the product can be reduced in size, restrictions on component arrangement can be prevented, and the mounting area can be reduced. Further, since the inorganic material constituting each insulating layer is not changed, mutual diffusion of different elements near the junction of each insulating layer due to the use of other materials (glass, other non-magnetic ceramic materials, etc.) is taken into consideration. This has the effect that the magnetic permeability of the fourth insulating layer can be lowered without necessity.

According to a sixth aspect of the present invention, the compounding ratio of the inorganic material and the resin in the fourth insulating layer before sintering is determined by comparing the first insulating layer, the second insulating layer, and the third insulating layer before sintering. Compared with the mixing ratio of the inorganic material and the resin in the insulating layer, the amount of the resin is larger than that of the inorganic material. According to this configuration, the resin is burned and removed at the time of sintering and the fourth insulating layer is formed. As the density decreases, the fourth insulating layer has a lower magnetic permeability than the first, second, and third insulating layers, and the fourth insulating layer further includes the fourth insulating layer laminated thereon. Since it is between the internal conductors formed on the one insulating layer, crosstalk between these internal conductors can be suppressed, and thereby the inductance value can be stabilized. In addition, since the crosstalk can be suppressed, a common ground electrode becomes unnecessary, so that the product can be reduced in size, restrictions on component arrangement can be prevented, and the mounting area can be reduced. Further, since the inorganic material constituting each insulating layer is not changed, mutual diffusion of different elements near the junction of each insulating layer due to the use of other materials (glass, other non-magnetic ceramic materials, etc.) is taken into consideration. This has the effect that the magnetic permeability of the fourth insulating layer can be lowered without necessity.

According to a seventh aspect of the present invention, the particle diameter of the inorganic material in the fourth insulating layer before sintering is determined by determining the particle size of the first insulating layer, the second insulating layer, and the third insulating layer before sintering. According to this configuration, the insulating layer made of an inorganic material whose particle size has been increased by heat treatment has a low density after sintering. Therefore, the density of the fourth insulating layer can be reduced, whereby the fourth insulating layer has a lower magnetic permeability than the first insulating layer, the second insulating layer, and the third insulating layer, Further, since the fourth insulating layer is located between the internal conductors formed on the laminated first insulating layer, crosstalk between these internal conductors can be suppressed, thereby stabilizing the inductance value. it can. In addition, since the crosstalk can be suppressed, a common ground electrode becomes unnecessary, so that the product can be reduced in size, restrictions on component arrangement can be prevented, and the mounting area can be reduced. Further, since the inorganic material constituting each insulating layer is not changed, mutual diffusion of different elements near the junction of each insulating layer due to the use of other materials (glass, other non-magnetic ceramic materials, etc.) is taken into consideration. This has the effect that the magnetic permeability of the fourth insulating layer can be lowered without necessity.

Hereinafter, a laminated inductor array according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of a laminated inductor array according to an embodiment of the present invention, FIG. 2A is a perspective view of the laminated inductor array, and FIG. FIG. 2C is a cross-sectional view taken along a line BB in FIG. 2A.

In FIGS. 1 and 2 (a) to 2 (c), 11
Is a first insulating layer having a through hole 12 filled with a conductive material such as Ag, and Ni-Cu-Zn as an inorganic material.
It consists of an oxide of a ferrite powder and a resin. 13
Reference numerals a, 13b, 13c, and 13d denote internal conductors, which are spiral inductor elements made of Ag, Ag-Pd, or the like, and are provided in specific regions on the upper and lower surfaces of the first insulating layer 11, respectively. The tip extends to one edge of the first insulating layer 11. At this time, the inner conductors 13a located on the upper and lower surfaces of the first insulating layer 11 are
By making electrical connection through the coil 2, a coil that is one spiral inductor element is formed. The same applies to the other internal conductors 13b, 13c, and 13d, thereby forming a total of four independent spiral inductor coils. A second insulating layer 14 is provided in two layers on the lower surface of the coil formed by the internal conductors 13a and 13b and the upper surface of the coil formed by the internal conductors 13c and 13d. 1
Reference numeral 5 denotes a third insulating layer, and the inner conductors 13a, 13b, 13
c, 13d are located above and below all independent spiral coils. That is, the inner conductor 13
A predetermined number is provided on the upper surface of the coil formed by a and 13b and the lower surface of the coil formed by the internal conductors 13c and 13d. From the above, the coil as the inductor element is sandwiched by the second insulating layer 14 and the third insulating layer 15. 16 is the fourth
The density after sintering is the first insulating layer 11, the second
And the third insulating layer 15 has a density lower than that of the second insulating layer 14, and does not contact the internal conductors 13a, 13b, 13c, and 13d between the two second insulating layers 14. Thus, one layer is formed. Of course, the fourth insulating layer 16 may have at least one layer. Reference numeral 17 denotes a sintered body, which includes a first insulating layer 11, a second insulating layer 14, a fourth insulating layer 16, a third insulating layer 15, and internal conductors 13a and 13a.
b, 13c, and 13d are provided by stacking and sintering. Reference numerals 18a, 18b, 18c, and 18d denote external electrodes, which are provided on a plurality of opposite side surfaces of the sintered body 17 and are provided at both ends of the independent spiral coils so as not to short-circuit the independent spiral coils. It is electrically connected.

As described above, in the laminated inductor array according to the embodiment of the present invention, the internal conductors 13a, which are juxtaposed upward with the second insulating layer 14 and the fourth insulating layer 16 interposed therebetween, are provided.
13b and the inner conductors 13c and 13d juxtaposed below are 2
It is arranged to have a story structure. That is, the first
The inner conductors 13a, 13b or 13c, 13d are formed on the insulating layer 11 of
b is above the second insulating layer 14 and the fourth insulating layer 16,
The internal conductors 13c and 13d are formed on the first insulating layer 1 formed below the second insulating layer 14 and the fourth insulating layer 16, respectively.
1. Also, the completed laminated inductor array has component external dimensions corresponding to the mounting area.

The density of the fourth insulating layer 16 after sintering is lower than the density of the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15 after sintering. Because the fourth
The magnetic permeability after sintering of the insulating layer 16 of the first insulating layer 11,
The magnetic permeability after sintering of the second insulating layer 14 and the third insulating layer 15 is lower.

Further, by forming the fourth insulating layer 16 between the two second insulating layers 14, the fourth insulating layer 16 is formed.
Are formed so as not to contact the internal conductors 13a, 13b, 13c, 13d. Thereby, each internal conductor 13a,
The inductance value in 13b, 13c, and 13d is not reduced by the fourth insulating layer 16 having low magnetic permeability after sintering. Therefore, the fourth insulating layer 16 is
It is necessary to form at least two or more second insulating layers 14 so as not to contact with 3a, 13b, 13c and 13d.

The manufacturing method of the laminated inductor array according to the embodiment of the present invention configured as described above will be described below with reference to the drawings.

FIGS. 3A to 3F are process diagrams showing a method for manufacturing a laminated inductor array according to an embodiment of the present invention.

First, as shown in FIG. 3A, a first insulating layer 11 is formed from a mixture of an oxide of a Ni—Cu—Zn ferrite powder, which is an inorganic material, and a resin by a doctor blade method. , The second insulating layer 14, the third
Is formed.

Next, as shown in FIG. 3B, a plurality of through-holes 12 are formed by drilling a predetermined portion of the first insulating layer 11, and a conductive material such as Ag is formed in the through-holes 12. Fill the material.

Next, as shown in FIG.
A plurality of internal conductors 13a, 13b, 13c, 1 which are spiral-shaped inductor elements made of g-Pd or the like.
3d is produced.

The internal conductors 13a, 13b, 13c,
13d may be spiral, meandering, or linear.

Next, as shown in FIG. 3D, a fourth insulating layer is formed by a doctor blade method from a mixture of a slurry of an oxide of a Ni—Cu—Zn ferrite powder as an inorganic material and a resin. 16 is manufactured. The sintered density of the fourth insulating layer 16 is smaller than the sintered density of the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15.

The density of the fourth insulating layer 16 after sintering over its entire surface is the first insulating layer 11 and the second insulating layer 1.
4. Even if the density of the third insulating layer 15 is not lower than the sintered density, at least the inner conductors 13a and 13b and the inner conductors located below the inner conductors 13a and 13b in the fourth insulating layer 16 The density after sintering of the portion corresponding to the position where 13c, 13d is opposed to the first insulating layer 11,
It is only necessary that the density of the second insulating layer 14 and the third insulating layer 15 be lower than the density after sintering.

Next, the internal conductors 13a located on the upper and lower surfaces of the first insulating layer 11 are electrically connected to each other through the through holes 12, thereby forming a coil as a spiral inductor element. Further, the other inner conductors 13b, 13
Similarly, a total of four spiral coils are formed for c and 13d. At this time, each spiral coil is made to be independent.

Next, as shown in FIG. 3E, at least two second insulating layers 14 are formed on the lower surfaces of the internal conductors 13a and 13b and the upper surfaces of the internal conductors 13c and 13d. At least one insulating layer 16 is formed between the second insulating layers 14 so as not to contact the internal conductors 13a, 13b, 13c, and 13d. And furthermore, the inner conductor 13
a, 13b, 13c and 13d, a third insulating layer 15 above and below all independent spiral coils.
Are laminated. Thereafter, after applying a pressure of about 70 kg / cm ² , the binder is burned and removed by heating in air, and sintered at a high temperature of about 850 to 1000 ° C.
7 is formed. At this time, the tips of the internal conductors 13a, 13b, 13c, 13d are exposed from one end surface of the sintered body 17.

Finally, as shown in FIG. 3 (f), the tips of the internal conductors 13a, 13b, 13c, 13d exposed from one end face of the sintered body 17 are provided on both sides of the sintered body 17 facing each other. The plurality of external electrodes 18 are electrically connected to the
The laminated inductor array according to one embodiment of the present invention is manufactured by forming a, 18b, 18c, and 18d. At this time, the plurality of external electrodes 18a, 18b, 18c, 18
d is such that the independent spiral coils are not short-circuited and electrically connected to both ends of the independent spiral coils.

The plurality of external electrodes 18a, 18b, 1
8c and 18d are made of low-melting metal plating such as end face electrodes, Ni plating and Sn plating. The end face electrode is made of Ag, Ag-Pd, Ni, Cu, or Ag and Ni so as to be electrically connected to both ends of each independent spiral coil.
Alternatively, a conductive paste of an alloy with Cu is applied and
It is formed by baking at 900 ° C. Further, it may be formed by vapor deposition, sputtering or the like. Furthermore, after forming the end face electrodes before sintering, they may be simultaneously fired together. Then, N is applied to cover this end face electrode.
i plating, and S
Low melting metal plating such as n plating is performed.

In FIGS. 1 and 2A to 2C, adjacent external electrodes 18a, 18b, 18c, 18d
, Adjacent internal conductors 13a, 13b, 13c, 13d exposed from one end face of the corresponding sintered body 17 respectively.
Are formed so that the positions of the fourth insulating layer 16 in the vertical direction are alternated, but are not necessarily exposed from one end faces of the sintered body 17 corresponding to the adjacent external electrodes 18a, 18b, 18c, 18d. Adjacent inner conductor 1
The third insulating layers 3a, 13b, 13c, and 13d need not be formed so that the positions of the fourth insulating layers 16 in the vertical direction are alternated.

FIG. 4 shows adjacent external electrodes 18a, 18b,
Adjacent internal conductors 13a, 13b, 1 exposed from one end surfaces of the sintered body 17 corresponding to 18c, 18d, respectively.
FIG. 5A is an exploded perspective view of the multilayer inductor array in which 3c and 13d are not formed so that the positions of the fourth insulating layer 16 in the vertical direction are alternately arranged. FIG. FIG. 5B is a sectional view taken along line AA of FIG. 5A, and FIG. 6 is a perspective view of the laminated inductor array (external electrodes 18a, 18b, 18c and 18d are not shown).

4, 5 (a), 5 (b), and 6 are given the same reference numerals as those of the laminated inductor array according to the embodiment of the present invention, and description thereof is omitted.

In the multilayer inductor array according to the embodiment of the present invention, the plurality of first insulating layers 1
1 is provided with internal conductors (in this case, two each),
And because this internal conductor is formed in a specific area,
Compared to the case where all the inner conductors 13a, 13b, 13c, 13d are formed on one first insulating layer 11, the crosstalk between the plurality of inner conductors in one first insulating layer is stacked. The crosstalk between the internal conductors formed on the plurality of first insulating layers can be suppressed, and the effect of stabilizing the inductance value can be obtained.

That is, in one first insulating layer 11, between a plurality of internal conductors 13a, 13b or 13c, 1
Since the distance between the inner conductors 3a and 3b does not approach each other, the distance between the plurality of internal conductors 13a and 13b arranged in parallel on one first insulating layer 11 is reduced.
Alternatively, there is a low magnetic coupling factor between 13c and 13d, and as a result, between the internal conductors 13a and 13b or 13c and 13d in one first insulating layer 11.
Since the crosstalk between them can be suppressed, the inductance value can be stabilized. Further, the plurality of inner conductors 13a, 13
b, 13c, and 13d, the distance between them is long, so that a low magnetic coupling is provided between the plurality of internal conductors 13a, 13b, 13c, and 13d arranged in parallel on the plurality of stacked first insulating layers 11. Factors, which result in multiple primary
Inner conductors 13a, 13b and 1 formed on the insulating layer 11 of FIG.
3c and 13d can be suppressed from crosstalk,
The inductance value can be stabilized.

Further, the plurality of first insulating layers 11
Internal conductors 13a, 13b and 13c, 13d formed in
Between the first insulating layer 11 and the second insulating layer 1
4. Fourth insulating layer 1 having a lower magnetic permeability than third insulating layer 15
6, the plurality of inner conductors 13a, 13b and 13c, 13c arranged in parallel on the plurality of stacked first insulating layers 11 are provided.
d has a lower magnetic coupling factor, and as a result, crosstalk between the internal conductors 13a, 13b and 13c, 13d formed in the plurality of first insulating layers 11 is further suppressed. Therefore, the inductance value can be further stabilized.

Further, as described above, each internal conductor 13a, 1
Since the crosstalk between 3b, 13c, and 13d can be suppressed, a common ground electrode is not required, so that the effects of reducing the size of the product, preventing restrictions on component arrangement, and reducing the mounting area can be obtained.

At least one of the plurality of internal conductors 13a, 13b, 13c, 13d formed on the first insulating layer 11 (two in this case) is formed on the second insulating layer 14 and the second insulating layer 14. Since it is formed on another first insulating layer 11 formed above or below the four insulating layers 16, the number of internal conductors formed on one first insulating layer 11 can be reduced. . Furthermore, since the completed laminated inductor array has component outer dimensions corresponding to the mounting area, the area in which the internal conductors 13a, 13b, 13c, and 13d can be formed can be increased.
The magnetic fields generated at a, 13b, 13c, and 13d can be increased, and thereby an effect that the inductance value can be easily increased can be expected.

Here, the following four methods are conceivable as methods for reducing the density of the fourth insulating layer 16 after sintering.

The compounding ratio of the plurality of oxides in the inorganic material constituting the fourth insulating layer 16 is determined by the first insulating layer 11 and the second insulating layer 11.
Is different from the mixing ratio of the plurality of oxides in the inorganic material forming the insulating layer 14 and the third insulating layer 15.

A void is provided in the fourth insulating layer 16.

The compounding ratio of the inorganic material and the resin in the fourth insulating layer 16 before sintering is determined by the first insulating layer 1 before sintering.
The amount of the resin is larger than that of the inorganic material in comparison with the mixing ratio of the inorganic material and the resin in the first, second and third insulating layers 14 and 15.

The particle diameter of the inorganic material in the fourth insulating layer 16 before sintering is adjusted to the particle diameter of the inorganic material in the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15 before sintering. Make it larger than the diameter.

FIG. 7 is a diagram showing the results of measuring the amount of current attenuation due to crosstalk in the laminated inductor array (1), which is another example of the embodiment of the present invention described above, and the conventional laminated inductor array. is there.

As an experimental method, the amount of current attenuation when currents having different frequencies were applied to each laminated inductor array was measured. This attenuation indicates the amount by which the current value is attenuated by the crosstalk. As the attenuation increases, the crosstalk due to the magnetic coupling generated between the adjacent internal conductors increases, and as a result, the inductance value decreases.

FIG. 8A is a cross-sectional view of a laminated inductor array which is another example of one embodiment of the present invention, and FIG. 8B is a cross-sectional view of a conventional laminated inductor array A, and FIG. (c) is a sectional view of a conventional laminated inductor array B. In addition, the reference numeral is another example of the embodiment of the present invention shown in FIG. 8A, and the laminated inductor array of is an embodiment of the present invention shown in FIGS. 1 and 2A to 2C. 1 (b) and 8 (c), the conventional multilayer inductor arrays A and B shown in FIGS.
0, the same reference numerals as in the conventional laminated inductor array shown in FIG.

The conventional laminated inductor array A is
It has a structure in which adjacent internal conductors 2 are formed at equal positions in the vertical direction inside the multilayer body. The conventional multilayer inductor array B is adjacent to a position alternately shifted in the vertical direction inside the multilayer body. It has a structure in which an internal conductor 2 is formed.

The dimensions of all the laminated inductor arrays are 3.2 mm in length, 1.6 mm in width, and 1.2 mm in height.
In this case, those having four elements built-in and having a DC resistance value of about 600Ω for each internal conductor were used. Of course, similar tendencies and results can be obtained by using different DC resistance values.

As the laminated inductor array in the above,
The weight ratio of the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15 is NiO: CuO: ZnO: Fe.
_{2 O 3 = 10: 10:} 15: using an inorganic material mixing ratio is 65 and a weight ratio with respect to the fourth insulating layer 16 is N
iO: CuO: ZnO: Fe ₂ O ₃ = 20: 10: 5: 6
An inorganic material having a compounding ratio of 5 was used. This sintered body
NiO: CuO: ZnO: Fe ₂ O ₃ = 10: 1 by weight ratio
The magnetic permeability is 85 for a sintered body laminated and fired only with an insulating layer having an inorganic material having a compounding ratio of 0:15:65.
% Decreased.

As the laminated inductor array in the above,
About 80 μm × about 500 μm is applied to the fourth insulating layer 16 before sintering.
Are provided. FIG. 9A is a perspective view of FIG.
9B is a sectional view taken along line AA in FIG. 9 (a) and 9 (b) are different from the embodiment of the present invention shown in FIG. 1 only in that a gap 19 is provided.

As the laminated inductor array in the above,
The weight ratio between the inorganic material and the resin before sintering in the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15 is 10
The ratio was 0: 5, and the weight ratio of the inorganic material to the resin in the fourth insulating layer 16 was 100: 15. In this sintered body, the resin is burned off during sintering, so that the density after sintering is reduced, and a sintered body obtained by laminating only an insulating layer having a weight ratio of inorganic material to resin of 100: 5 is fired. On the other hand, the density after sintering decreased by 10% and the magnetic permeability decreased by 70%.

As the laminated inductor array in the above,
The average particle size of the inorganic material before sintering in the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15 is 1 μm, and the average particle size of the inorganic material before sintering in the fourth insulating layer 16 is The one having a particle size of 5 μm was used. Since the sintered body has a large particle diameter of the inorganic material, the density after sintering becomes small. Has a density of 5% and a magnetic permeability of 30.
% Decreased.

As is apparent from FIG.
In the multilayer inductor array which is another example of the embodiment of the present invention, the current value attenuates less than the conventional multilayer inductor array. That is, crosstalk due to magnetic coupling generated between adjacent internal conductors is small, and the inductance value is high.

In the conventional example B, since the adjacent internal conductors 2 are formed at positions alternately displaced from each other in the vertical direction inside the laminated body, the distance between the adjacent internal conductors 2 is increased, thereby increasing the distance between the adjacent internal conductors 2. Since the magnetic coupling between the internal conductors 2 is smaller than that of the conventional example A, it can be estimated that the conventional example B has smaller crosstalk than the conventional example A.

In the above-described laminated inductor array, the magnetic permeability between the internal conductors formed in the laminated first insulating layer is higher than that of the first, second, and third insulating layers. Since a low fourth insulating layer can be formed, a low magnetic coupling factor exists between the plurality of internal conductors 13a, 13b, 13c, and 13d arranged in parallel with the plurality of stacked first insulating layers 11. As a result, the internal conductors 13a, 13b, 13 formed on the plurality of first insulating layers 11
Since the crosstalk between c and 13d can be suppressed, the inductance value can be stabilized. In addition to this, since the crosstalk can be suppressed in this way, a common ground electrode is not required, so that the effects of reducing the size of the product, preventing restrictions on component arrangement, and reducing the mounting area can be obtained. .

Further, the above-mentioned items 1 to 1 indicate the first insulating layer 1
Since the inorganic materials constituting the first, second insulating layers 14, the fourth insulating layers 16, and the third insulating layers 15 are not changed, other materials (glass, other nonmagnetic ceramic materials, and the like) are used. First insulating layer 11, second insulating layer 1 by using
The effect that the magnetic permeability of the fourth insulating layer 16 can be reduced without having to consider the mutual diffusion of different elements in the vicinity of each junction of the fourth, fourth insulating layer 16 and the third insulating layer 15 can also be expected. . However, when mutual diffusion of different elements near each junction of the first insulating layer 11, the second insulating layer 14, the fourth insulating layer 16, and the third insulating layer 15 occurs, the fourth insulating layer 16 Since the composition changes, the magnetic permeability of the fourth insulating layer 16 is not always lower than that of the first insulating layer 11, the second insulating layer 14, and the third insulating layer 15.

In the above-described embodiment of the present invention, the upper internal conductors 13a and 13b and the lower internal conductor 13 with the second insulating layer 14 and the fourth insulating layer 16 interposed therebetween.
Although the description has been given of the case where c and 13d are arranged so as to have a two-story structure, each internal conductor is arranged so as to have a three-story or more structure through two or more fourth insulating layers 16. Also, an effect equivalent to that of the above-described embodiment of the present invention can be obtained. Also, the number of internal conductors is not necessarily four.

[0071]

As described above, the laminated inductor arrays of the present invention have component external dimensions corresponding to the required mounting area, and are arranged in parallel so as to have a low magnetic coupling factor within the component external dimensions. A plurality of first insulating layers each having an internal conductor that is an inductor element formed in a plurality of specific regions;
A second insulating layer provided on upper and lower surfaces of the first insulating layer to sandwich a plurality of inductor elements provided on the first insulating layer; and a second insulating layer provided on the upper and lower surfaces of the first insulating layer. A plurality of inductor elements provided on the first insulating layer sandwiched between the first insulating layer and the third insulating layer are laminated with a low magnetic coupling factor. According to this configuration, one first Since crosstalk between the plurality of internal conductors in the insulating layer and crosstalk between the internal conductors formed in the stacked first insulating layers can be suppressed, the inductance value can be stabilized. In addition to this,
Since the crosstalk can be suppressed, a common ground electrode is not required. Therefore, there is an excellent effect that the product can be reduced in size, restrictions on component arrangement can be prevented, and the mounting area can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a multilayer inductor array according to an embodiment of the present invention.

2A is a perspective view of the multilayer inductor array, FIG. 2B is a cross-sectional view taken along line AA in FIG. 2A, and FIG. 2C is a cross-sectional view taken along line BB in FIG. 2A.

FIGS. 3A to 3F are manufacturing process diagrams showing a manufacturing method of the multilayer inductor array;

FIG. 4 is a view showing the present invention in which adjacent internal conductors exposed from one end surfaces of sintered bodies respectively corresponding to adjacent external electrodes are not formed such that positions of a fourth insulating layer in the vertical direction are alternately arranged; Exploded perspective view of a multilayer inductor array according to one embodiment

5A is a perspective view of the laminated inductor array, and FIG. 5B is a cross-sectional view taken along line AA in FIG.

FIG. 6 is a perspective view of the multilayer inductor array.

FIG. 7 is a diagram showing the results of measuring the amount of current attenuation due to crosstalk in the laminated inductor array of (1), which is another example of the embodiment of the present invention, and the conventional laminated inductor array.

8A is a cross-sectional view of a multilayer inductor array according to another embodiment of the present invention, and FIG. 8B is a cross-sectional view of a conventional multilayer inductor array A. FIG. Sectional view

9A is a perspective view of a laminated inductor array as another example according to an embodiment of the present invention, and FIG. 9B is a sectional view taken along line AA in FIG. 9A.

FIG. 10 is a perspective view of a conventional multilayer inductor array.

FIG. 11 is an exploded perspective view of the multilayer inductor array.

FIGS. 12A to 12E are manufacturing process diagrams showing a method for manufacturing the multilayer inductor array;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 1st insulating layer 13a, 13b, 13c, 13d Internal conductor 14 2nd insulating layer 15 3rd insulating layer 16 4th insulating layer 18a, 18b, 18c, 18d External electrode 19 Void

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Washi ▲ Saki ▼ Tomoyuki 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Tatsuya Nakamori 1006 Kadoma Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. In-house (72) Inventor Kazuo Oishi 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.F-term (reference) 5E070 AA01 AA05 AB01 BA12 CB13 CB17 CB20 EA01 EB03

Claims (7)

[Claims] An internal component, which has inductor external dimensions corresponding to a required mounting area and is provided in a plurality of specific regions juxtaposed so as to have a low magnetic coupling factor within the external dimensions of the component, respectively. A plurality of first insulating layers on which conductors are formed, and a second insulating layer disposed on upper and lower surfaces of the first insulating layer so as to sandwich a plurality of inductor elements provided on the first insulating layer And a third insulating layer, wherein a plurality of inductor elements disposed on the first insulating layer sandwiched between the second insulating layer and the third insulating layer are stacked with a low magnetic coupling factor. Inductor array. 2. The method according to claim 1, wherein at least one fourth insulating layer having a lower magnetic permeability than the first insulating layer, the second insulating layer, and the third insulating layer is formed between the plurality of second insulating layers. Item 2. The multilayer inductor array according to Item 1. 3. The density of the fourth insulating layer after sintering is smaller than the density of the first insulating layer, the second insulating layer, and the third insulating layer after sintering. The laminated inductor array as described in the above. 4. A compounding ratio of a plurality of oxides in an inorganic material forming a fourth insulating layer is determined by changing a mixing ratio of a plurality of oxides in an inorganic material forming a first insulating layer, a second insulating layer, and a third insulating layer. 3. The multilayer inductor array according to claim 2, wherein the mixing ratio of the plurality of oxides is different. 5. The multilayer inductor array according to claim 2, wherein a void is provided in the fourth insulating layer. 6. The compounding ratio of the inorganic material and the resin in the fourth insulating layer before sintering is determined by the ratio of the inorganic material in the first insulating layer, the second insulating layer, and the inorganic material in the third insulating layer before sintering. 3. The multilayer inductor array according to claim 2, wherein the amount of the resin is larger than that of the inorganic material as compared with the mixing ratio with the resin. 7. The particle size of the inorganic material in the fourth insulating layer before sintering is changed to the particle size of the inorganic material in the first insulating layer, the second insulating layer, and the third insulating layer before sintering. 3. The multilayer inductor array according to claim 2, wherein the size of the multilayer inductor array is increased.