JP2002373810A - Chip type common mode choke coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip type common choke coil capable of increasing the number of turns of coil windings easily forming a pair, producing high impedance, and producing high magnetic coupling between the coil windings. SOLUTION: In coil windings 11, 12 forming a pair in a structure, insulating layers 2, 3, 4, 5, 6 and spiral conductive thin films 11a, 12a, 11b, 12b are stacked in the direction of thickness on the principal surface of an insulating substrate 1. The coil winding 11 is formed by connecting in series the two layers of the spiral conductive thin films 11a, 11b, and the coil winding 12 is formed by connecting in series the two layers of the spiral conductive thin films 12a, 12b. Ends of the two layers of the spiral conductive thin films are connected to each other, and the other ends thereof are connected to external electrodes, respectively. The one layer 12a of the two spiral conductive thin films constructing one coil winding 12 is interposed between the two spiral conductive thin films 11a, 11b constructing the other coil winding 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component used as a countermeasure for noise invading various electronic devices, and more particularly to a chip type common mode choke coil.

[0002]

2. Description of the Related Art Conventionally, a coil component disclosed in Japanese Patent Application Laid-Open No. 8-203737 is known as this kind of electronic component using a thin film forming method. This coil part is shown in FIG.
As shown in FIG. 9 and FIG.
1, the lead electrodes 53 and 54, the insulating layer 42, the first coil conductor 51, the insulating layer 43, the second coil conductor 52, and the insulating layer 44 are arranged in this order, and are sandwiched by the magnetic substrate 45 from the upper surface. In addition, as shown in FIG.
0,45 are formed on the side surfaces. The through-hole 56 connects the first coil conductor 51 and the extraction electrode 53 to form a first coil winding.
Reference numerals a and 57b denote connecting the second coil conductor 52 and the extraction electrode 54 to form a second coil winding.

[0003]

In the structures shown in FIGS. 8 and 9, when a high impedance value is required, or in order to cope with the miniaturization of a chip, a coil conductor or an extraction electrode constituting a coil winding is required. It is necessary to make the conductor width narrower, and there is a problem in that the production yield is lowered and the characteristics such as magnetic coupling are lowered.

In addition, the ratio of the extraction electrode portion and the external electrode connection portion of the coil conductor occupying all the conductors in the two coil windings to the entire conductor is large, and the difference in impedance between the superposed coil windings becomes large. Adversely affects the normal mode characteristics, such as generation of noise.

[0005] A first object of the present invention is to solve the above problems,
By forming a pair of coil windings of a spiral conductive thin film by a thin film forming method without forming an extraction electrode pattern portion, it is possible to easily increase the number of turns of each coil winding and obtain high impedance. It is an object of the present invention to provide a chip-type common mode choke coil capable of achieving high magnetic coupling between paired coil windings.

A second object of the present invention is to provide a chip type common mode choke coil capable of increasing the impedance of a pair of coil windings and reducing the difference in inductance between the paired coil windings. To provide.

[0007] Other objects and novel features of the present invention will be clarified in embodiments described later.

[0008]

In order to achieve the above object, a chip-type common mode choke coil according to the present invention has an insulating layer and a spiral conductive thin film stacked in a thickness direction on a main surface of an insulating substrate. A pair of coil windings is formed in a structure, and each coil winding is composed of a series connection of two layers of spiral conductive thin films, one end of the two layers of spiral conductive thin films is connected, and the other end is an external electrode. And one of the two spiral conductive thin films forming the other coil winding is interposed between the two layers of the spiral conductive thin film forming the one coil winding. It is characterized by.

In the above-mentioned chip-type common mode choke coil, the insulating substrate may be a magnetic substrate, and a magnetic material may be disposed on the upper side, and the pair of coil windings may be sandwiched between the magnetic substrate and the magnetic material. Good.

Further, the insulating substrate is a magnetic substrate, and an opening is formed in the insulating layer at a position to be a central portion and a peripheral portion of each spiral conductive thin film, and a magnetic material is also provided in the opening to form a closed magnetic circuit structure. It may be.

Further, it is preferable that each spiral conductive thin film has a spiral winding portion and an external electrode extraction portion, and the opening in the peripheral portion is located inside the external electrode extraction portion.

It is preferable that the magnetic material is disposed on a region including a helical wrap around the helical conductor thin film other than the external electrode extraction portion.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a chip type common mode choke coil according to the present invention will be described below with reference to the drawings.

FIGS. 1 and 2 show a first embodiment of a chip type common mode choke coil according to the present invention. In actual manufacturing, a plurality of chip-type common mode choke coils are simultaneously manufactured on a substrate.
This will be described in terms of elements.

As shown in FIGS. 1 and 2, a chip-type common mode choke coil is formed on a main surface of an insulating substrate 1 by a pair of coil windings 11, 1 having a laminated structure of an insulating layer and a conductive thin film.
2, a spiral conductive thin film 11a as a lower coil conductor of the insulating layer 2, the first coil winding 11,
Insulating layer 3, spiral conductive thin film 12a as lower coil conductor of second coil winding 12, insulating layer 4, spiral conductive thin film 11 as upper coil conductor of first coil winding 11
b, an insulating layer 5, a spiral conductor thin film 12b as an upper layer coil conductor of the second coil winding 12, and an insulating layer 6 are sequentially provided. The first coil winding 11 is formed of a spiral conductor thin film 11a, 1 as a lower and upper coil conductor.
1b, and the second coil winding 12 is
Spiral conductor thin film 1 as lower and upper coil conductors
2a, 12b, and a two-layer spiral conductor thin film 11a, 1 constituting the first coil winding 11.
One of the two layers of the spiral conductive thin films 12a and 12b constituting the second coil winding 12 (that is, the thin film 12a) is interposed between the layers 1b.

As shown in FIG. 2, external electrodes (terminal electrodes) 20 are formed on side surfaces of the insulating substrate 1 (partly extending to the lower surface of the substrate 1 and the upper surface of the insulating layer 6). .

Each of the spiral conductive thin films 11a, 11b, 12
Reference numerals a and 12b denote external electrode extraction portions Y which are extraction ends for connection to external electrodes 20 provided on the side surface portion of the insulating substrate 1.
The other parts are helical circling parts X, and are mostly formed by helical circulating parts.

The spiral conductive thin films 11a, 12a, 11b, and 12b provided on the insulating layers 2, 3, 4, and 5 are formed by a thin film forming method, and the lower and upper spiral conductive thin films 11a, 12a, 11b, and 12b are formed.
a, 11b are through holes 15a, 15 of the insulating layers 3, 4;
b, one end is connected to each other, and the other end is connected to each of the external electrodes 20 on the side surface of the insulating substrate. Similarly,
The lower and upper spiral conductive thin films 12a and 12b have one ends connected to each other via through holes 16a and 16b in the insulating layers 4 and 5, and the other ends connected to the external electrodes 20 on the side surfaces of the insulating substrate.

The insulating substrate 1 is preferably a low dielectric constant ceramic, resin or the like. And the material of each spiral conductive thin film is Cu,
A metal having excellent electric conductivity such as Ag or Al is employed.

Next, a manufacturing procedure of the chip type common mode choke coil according to the present embodiment will be described with reference to FIG.

An insulating layer 2 is formed on an insulating substrate 1. As a forming method, a spin coating method, a dipping method, a spray method, a printing method, or the like is employed.

Then, a conductive thin film is formed on the insulating layer 2 and the spiral conductive thin film 11 is formed by photolithography.
The pattern a is formed. Sputtering, evaporation,
A thin film forming method such as plating is employed. The photolithography method uses a photosensitive resist and after exposure and development,
Unnecessary metal portions are etched, and then the resist is stripped.

Next, an insulating layer 3 is formed. The forming method is the same as that of the insulating layer 2, except that the spiral conductive thin films 11a and 11b are formed.
The through holes 15a are formed by development using a photolithography method.

Next, the spiral conductive thin film 12a is formed and patterned. The construction method is the same as that of the spiral conductive thin film 11a.

After that, the insulating layer 4 is formed by the same method as the insulating layer 3. Here, through holes 15b and 16a are formed by development using a photolithography method. The through hole 15b is for connecting the spiral conductive thin films 11a and 11b, and the through hole 16a is for the spiral conductive thin films 12a and 12b.
This is for connection with b.

Next, the spiral conductive thin film 11b is formed and patterned. The construction method is the same as that of the spiral conductive thin film 11a, whereby the spiral conductive thin films 11a and 11b are connected in series through the through holes 15a and 15b.
Is obtained.

After that, the insulating layer 5 is formed by the same method as the insulating layer 3. Here, the through-hole 16b is formed by development using a photolithography method. Through hole 16
b is for connection between the spiral conductive thin films 12a and 12b.

Next, film formation and patterning of the spiral conductive thin film 12b are performed. The construction method is the same as that of the spiral conductive thin film 12a, whereby the spiral conductive thin films 12a and 12b are connected in series through the through holes 16a and 16b.
Is obtained.

Thereafter, an insulating layer 6 is formed on the entire surface by the same method.

The above description is for one element.
In practice, a plurality of elements are simultaneously produced on a substrate. After the device manufactured on this substrate is cut into one element shape, external electrodes 20 are formed on the side surface of the insulating substrate 1 for one element, and a chip type common mode choke coil is completed.

According to the first embodiment, the following effects can be obtained.

(1) The pair of coil windings 11 and 12 are
Almost all are formed with two layers of spiral conductive thin films that spirally spiral, respectively, so that the number of turns of each coil winding can be easily increased, and high impedance can be obtained. Further, the width of each conductor can be increased, and high magnetic coupling can be obtained.

(2) 2 constituting one coil winding 11
Two layers of the spiral conductive thin films 12a, 1 constituting the other coil winding 12 between the layers of the spiral conductive thin films 11a, 11b
One of the coil windings 2b is interposed, so that a high magnetic coupling can be obtained between the pair of coil windings.

(3) Almost all of the spiral conductive thin films are spiral wraps, and it is easy to reduce the impedance difference between the two coil windings.

FIG. 3 shows a second embodiment of the present invention, in which the pattern of the spiral conductive thin films of the coil windings 11 and 12 forming a pair is changed, and the first coil winding 11
Is composed of a series connection of spiral conductor thin films 11c and 11d as its lower and upper coil conductors, and a second coil winding 12 is formed of a series of spiral conductor thin films 12c and 12d as its lower and upper coil conductors. Consists of connections.

The other structure is the same as that of the first embodiment, and the same or corresponding parts are denoted by the same reference characters and description thereof will be omitted.

FIG. 4 shows a third embodiment of the present invention.
In this case, a magnetic substrate 21 made of ferrite, composite ferrite, or the like is used as an insulating substrate, and a magnetic material (a magnetic substrate may be used) 22 of the same material is further disposed and fixed above the uppermost insulating layer 6. The two coil windings 11 and 12 are sandwiched between a magnetic substrate 21 and a magnetic material 22.

The rest of the configuration is the same as that of the first embodiment, and the same or corresponding parts are denoted by the same reference characters and description thereof is omitted.

According to the third embodiment, the first and second coil windings 11 and 12 are connected to the magnetic substrate 21 and the magnetic material 2.
2, the impedance can be increased by each coil winding.

FIG. 5 shows a fourth embodiment of the present invention, in which a part of an upper magnetic material 22 is joined to a lower magnetic substrate 21 to form a closed magnetic circuit structure as shown in FIG. Show the case. In this case, the manufacturing procedure is the same as that of the third embodiment, except for the pattern shape of the insulating layers 2, 3, 4, 5, and 6. When the insulating layer openings 2a, 3a, 4a, 5a, 6a are formed in the respective insulating layer forming regions in the third embodiment by development so as to overlap each other, and when the upper magnetic material 22 is formed in a layered form, The insulating layer openings 2a, 3a, 4a,
The magnetic material 22 enters the insides 5a and 6a and is joined to the lower magnetic substrate 1 to form a closed magnetic circuit structure. Here, of the coil windings 11 and 12 (each of which is connected in series with two layers of spiral conductive thin films), each spiral conductive thin film 11a, 1
The openings 2a, 3a, 4a, 5a, and 6a are located at the center of the spirally wound portion X of 1b, 12a, and 12b and at the outer peripheral portion of the spirally wound portion X and inside the external electrode extraction portion Y. As a result, a closed magnetic circuit is formed so as to surround a portion where the winding directions of the coil windings 11 and 12 are aligned.

When a magnetic substrate is used as the upper magnetic material 22, the insulating layer openings 2a, 3a, 4a, 5 inside the central portions of the insulating layers 2 to 6 and the external electrode extraction portion Y.
It is also possible to adopt a structure in which a magnetic material is embedded in a and 6a and a magnetic substrate is attached from the upper surface.

According to the fourth embodiment, a pair of coil windings 11 and 12 (series connection of spiral conductive thin films)
Of these, the closed magnetic path is formed so as to surround the spirally wound portion X having the same winding direction, so that the impedance of each coil winding can be further increased.

FIG. 7 shows a fifth embodiment of the present invention, in which a part of an upper magnetic material 23 is joined to a lower magnetic substrate 21 to form a closed magnetic circuit structure. The structure which devised the shape and arrangement of is shown. In this case, the magnetic substrate 2
1, the coil windings 11 and 12, the insulating layers 2 to 6 etc.
In this embodiment, the width of the magnetic material 23 is smaller than that of the magnetic substrate 21, and the magnetic material 23 has a spiral shape in which the spiral conductor thin films 11a, 11b, 12a, 12b are wound in the same winding direction. It is selectively disposed so as to cover the circling portion X and not to cover the external electrode extraction portion Y, and forms a closed magnetic circuit so as to surround the helical circulating portion X.

According to the fifth embodiment, a pair of coil windings 11 and 12 (series connection of spiral conductive thin films)
Among them, a closed magnetic circuit is formed so as to surround the spirally wound portion X having the same winding direction, and a high impedance can be obtained in a region of the spirally wound portion X by a closed magnetic circuit structure in which magnetic materials exist above and below. However, the portion including the external electrode extraction portion Y where the impedance difference is easily generated has a low impedance because the magnetic material is present only on the lower surface, and the impedance difference between the two coil portions of the common mode choke coil is small. Become.

Although the embodiments of the present invention have been described above, it is obvious to those skilled in the art that the present invention is not limited to the embodiments and that various modifications and changes can be made within the scope of the claims. For example, the present invention is also applicable to a structure in which the spiral conductive thin film pattern is changed or the shape of the magnetic material is changed, and two or more pairs of coil windings are formed on a substrate.

[0046]

As described above, according to the present invention,
By forming a pair of coil windings with a spiral conductor thin film spirally wound by the thin film formation method, it is possible to cope with miniaturization and high impedance, and it is possible to make the impedance uniform and normal mode characteristics A small chip-type common mode choke coil with excellent magnetic coupling that does not cause noise to be realized.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of a chip-type common mode choke coil according to the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is an exploded perspective view showing a second embodiment of the present invention.

FIG. 4 is an exploded perspective view showing a third embodiment of the present invention.

FIG. 5 is an exploded perspective view showing a fourth embodiment of the present invention.

FIG. 6 is a side sectional view showing a closed magnetic circuit structure according to a fourth embodiment.

FIG. 7 is an exploded perspective view showing a fifth embodiment of the present invention.

FIG. 8 is an exploded perspective view of a conventional technique.

FIG. 9 is a perspective view of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating substrate 2,3,4,5,6 Insulating layer 2a, 3a, 4a, 5a, 6a Opening 11,12 Coil winding 11a, 11b, 12a, 12b Spiral conductor thin film 20 External electrode 21 Magnetic substrate 22, 23 Magnetic material 15a, 15b, 16a, 16b Through hole

Claims (5)

[Claims] 1. A pair of coil windings having a structure in which an insulating layer and a spiral conductive thin film are stacked in a thickness direction on a main surface of an insulating substrate, and each coil winding is a two-layer spiral conductive thin film. Are connected in series, one end of the two-layer spiral conductive thin film is connected to each other, and the other end is connected to the external electrode, respectively, and between the two spiral conductive thin films forming one coil winding. Characterized in that one of the two layers of the spiral conductive thin film constituting the other coil winding is interposed therebetween. 2. The chip-type common mode choke according to claim 1, wherein said insulating substrate is a magnetic substrate, and a pair of coil windings is sandwiched between said magnetic substrate and said magnetic material by further arranging a magnetic material on the upper side. coil. 3. The closed magnetic circuit, wherein the insulating substrate is a magnetic substrate, an opening is formed in the insulating layer at a position to be a central portion and a peripheral portion of each spiral conductive thin film, and a magnetic material is also provided in the opening. 3. The chip-type common mode choke coil according to claim 2, which has a structure. 4. The chip-type common mode according to claim 3, wherein each spiral conductive thin film includes a spiral circling portion and an external electrode extraction portion, and the opening in the peripheral portion is located inside the external electrode extraction portion. choke coil. 5. The chip-type common mode choke coil according to claim 4, wherein said magnetic material is disposed on a region including a helical wrap around the helical conductor thin film other than the external electrode extraction portion.