JP2003332140A - Chip common mode choke coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chip common mode choke coil superior in mechanical strength of an outside electrode at the same time by solving an electrical connection problem of the outside electrode and a coil conductor. <P>SOLUTION: The chip common mode choke coil forms the same shaped first and second conductors 11 and 12 making pairs on the front and rear of an insulating layer 1, sandwiches the first and second conductors 11 and 12 with magnetic components 4 and 5 from an upper layer, and has a structure forming a coil conductor making the pairs only by the conductors 11 and 12. Both ends 11a, 11b, 12a and 12b selves of each conductor 11 and 12 constitute mounting outside electrodes respectively, which are formed so that the formation face of each conductor 11 and 12 is vertical to a mounting surface. <P>COPYRIGHT: (C)2004,JPO

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 against noise that enters various electronic devices, and more particularly to a chip type common mode choke coil which can be easily manufactured and is inexpensive.

[0002]

2. Description of the Related Art Conventionally, a laminated type is known as a chip type common mode choke coil. In this component, a magnetic sheet for a first coil, in which a coil conductor pattern is formed on the surface of a magnetic sheet such as ferrite to form a first coil, and a magnetic sheet for a second coil, which similarly forms a second coil, are alternately arranged. It is a laminated structure.

A coil component disclosed in Japanese Patent Laid-Open No. 8-203737 is known as one using a thin film method. As shown in FIGS. 10 and 11, this coil component includes a magnetic substrate 40, an insulating layer 41, and an extraction electrode 5 on the magnetic substrate 40.
3, 54, insulating layer 42, first coil conductor 51, insulating layer 4
3, the second coil conductor 52 and the insulating layer 44 are sequentially arranged and sandwiched by the magnetic substrate 45 from the upper surface thereof. Also,
The external electrode (terminal electrode) 55 is formed on the magnetic substrate 4 as shown in FIG.
It is formed on the side surface of 0, 45. The through hole 56 is for connecting the first coil conductor 51 and the extraction electrode 53 to form a first coil winding, and the through holes 57a and 57b are the second coil conductor 52 and the extraction electrode 54. And to connect to form a second coil winding.

[0004]

In the conventional laminated type and thin film type products described above, a plurality of elements are simultaneously formed on a sheet or a substrate, cut into chips after pattern formation is completed, and exposed at the time of cutting. The conductor part of the chip body is used for connection with the external electrode (terminal electrode).

At this time, the connecting surface of the conductor portion used for connection with the external electrode has a small area, and a problem easily occurs in terms of electrical contact. In addition, depending on the substrate and the sheet that form the chip body, it is difficult to secure the adhesion with the external electrode material, and problems such as peeling of the external electrode portion during mounting are likely to occur. Further, depending on the material used for the chip body, there are large restrictions on the temperature when forming the external electrodes.

In view of the above problems, it is an object of the present invention to solve the problem of electrical connection between an external electrode and a coil conductor and to provide a chip type common mode choke coil which is excellent in mechanical strength of the external electrode at the same time. And

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

[0008]

In order to achieve the above-mentioned object, a chip type common mode choke coil according to the invention of claim 1 of the present application comprises a first and a second having the same shape which are paired on the front and back surfaces of an insulating layer. This is a structure in which a conductor is formed, the first and second conductors are sandwiched by a magnetic material from the upper layer, and a coil conductor that forms a pair only with the conductor is formed, and both ends of each conductor themselves constitute mounting external electrodes. The mounting external electrode is characterized in that the surface on which each conductor is formed is perpendicular to the mounting surface.

A chip-type common mode choke coil according to a second aspect of the present invention is characterized in that, in the first aspect, a solder connection layer is formed on the surface of the mounting external electrode by plating or the like.

The chip-type common mode choke coil according to the invention of claim 3 is characterized in that, in claim 1 or 2, the insulating layer has a thickness of 100 μm or more.

The chip type common mode choke coil according to the invention of claim 4 of the present application is characterized in that, in claim 1, 2, or 3, the insulating layer is an insulating resin sheet of polyimide, epoxy resin or the like.

The chip type common mode choke coil according to the invention of claim 5 is characterized in that, in claim 1, 2 or 3, the insulating layer is an insulating substrate such as a glass-based epoxy resin substrate. .

The chip-type common mode choke coil according to the invention of claim 6 of the present application is the invention of claim 1, 2, 3, 4 or 5.
In the above, a part of the first and second conductors is covered with a closed magnetic circuit including the magnetic body.

A chip-type common mode choke coil according to a seventh aspect of the present invention is the chip-type common mode choke coil according to the first, second, third, fourth, fifth or sixth aspect, in which the pair of first and second conductors of the same shape forming the pair is formed. The feature is that a plurality of pairs are provided.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a chip type common mode choke coil according to the present invention will be described below with reference to the drawings.

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

1 and 2, the chip-type common mode choke coil has first and second coil conductors 11 and 12 of the same shape formed on both front and back surfaces of the insulating layer 1, and the insulating layer 1 and the first and second coil conductors are formed. The magnetic bodies (magnetic substrate etc.) 4 and 5 are provided so as to sandwich the two coil conductors 11 and 12, and
End portions 11a, 11b, 12a of the coil conductors 11, 12;
12b is exposed as a mounting external electrode (terminal electrode) in the chip body 10 of FIG.

In this chip-type common mode choke coil, only the conductors 11 and 12 on the front and back surfaces of the insulating layer 1 constitute the pair of first and second coil conductors, and both ends thereof are for mounting. It is a structure that also serves as an external electrode,
The first coil conductor 11 integrally has conductor ends 11a and 11b formed in an inverted L shape on both sides of a linear conductor portion as mounting external electrodes, and similarly, the second coil conductor 12 is also provided.
Has conductor end portions 12a and 12b formed in an inverted L shape on both sides of the linear conductor portion integrally as mounting external electrodes.

The pair of first and second coil conductors 1
The insulating layer 1 between 1 and 12 is made of a resin sheet of polyimide resin, epoxy resin, or the like, FR-4 (epoxy resin laminated substrate of heat-resistant glass base material), etc. in consideration of workability, insulation properties, corrosion resistance to conductors, etc. used.

Further, the first and second coil conductors 11 and 12
As the material, a metal having excellent electric conductivity such as Cu, Ag and Al is adopted. It is desirable that the thickness of each coil conductor 11, 12 is thicker than the insulating layer 1 and about several hundreds μm in order to serve also as an external electrode for mounting.

Further, the first and second coil conductors 1 forming a pair
Magnetic materials such as sintered ferrite, composite ferrite, and magnetic thin films are used for the magnetic bodies 4 and 5 that sandwich the magnetic materials 1 and 12 from both sides. In order to integrate the magnetic bodies 4 and 5, an insulating adhesive or sealing member 6 such as an adhesive agent or resin sealing (including sealing by the composite ferrite itself) is used together, if necessary.

As shown in FIG. 2, conductor end portions 11a, 11b, 12a and 12 of the first and second coil conductors 11 and 12 are shown.
b is configured as a mounting external electrode exposed on the side surface and the bottom surface when the magnetic bodies 4 and 5 are integrated and then cut into a chip size to form a chip body 10. Are provided so as to be perpendicular to the mounting surface (the surface to be mounted on the mounting board of the other side).

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

A pair of first and second coil conductors 11 and 12 are formed on both surfaces (front and back surfaces) of the insulating layer 1 (sheet or substrate). As a forming method, a thin film forming method such as sputtering, vapor deposition, plating or the like is adopted, or a copper clad laminate is used. For patterning, there is a method using a photolithography method. In the photolithography method, a photosensitive resist is used and after exposure and development, unnecessary metal portions are etched, and then the resist is peeled off. Alternatively, if the conductor is desired to be thick, there is also a method in which after resist patterning, a pattern is formed by an additive method and then the resist is peeled off. The film formation at this time can be efficiently performed by the front and back simultaneous processing, and the patterning can also be performed by the simultaneous front and back simultaneous exposure and development to efficiently and accurately form the coil conductor pattern.

Although not shown in the drawing, the coil conductors 11 and 12 and the magnetic bodies 4 and 5 are provided as necessary for conductor protection.
An insulating layer may be formed between them.

After the coil forming portion (the portion including the insulating layer 1 and the coil conductors 11 and 12) manufactured by the above-mentioned method is sandwiched by the magnetic bodies 4 and 5, sealing (resin sealing or resin as a magnetic material) is performed. The layered structure of the chip-type common mode choke coil is completed by encapsulating with a composite material containing (1) or by forming magnetic thin films on both sides as magnetic bodies.

Although the above description is for one element, in reality, a plurality of elements are simultaneously formed on a sheet or substrate. After cutting this sheet or the one produced on the substrate into one element shape, a chip type common mode choke coil having the conductor end exposed on the side surface and the bottom surface as an external electrode is completed.

At this time, the conductor end portions 11a, 11b, 12a, 12b serving as mounting external electrodes cause the coil conductor forming surface (the surface on which the first and second coil conductors 11 and 12 are formed) to be on the opposite side mounting substrate. It becomes perpendicular to the mounting surface for.
Further, in consideration of solderability at the time of mounting the chip type common mode choke coil, at least the exposed surface of the conductor end portions 11a, 11b, 12a, 12b as the mounting external electrodes is soldered by a treatment such as tin or solder plating. It is effective to form a connection layer.

Further, in order to secure the required distance between the mounting external electrodes, the thickness of the insulating layer 1 is L1- (100 μm × 2) ≧ t1 ≧ 100 μm (1) where tl is the insulating layer between coil conductors It is necessary to satisfy the thickness Ll: the width of the chip element body (the entire width of the external electrode forming surface: see FIG. 2). The reason why 100 μm is set as the lower limit reference value is as follows.

The mounting position accuracy of a general electronic component mounter is about ± 100 μm, and in consideration of the positional deviation at the time of mounting, the external electrode interval needs to be at least 100 μm or more. For this purpose, the thickness of the insulating layer 1 which is the distance between the external electrodes needs to be 100 μm or more as a minimum value.

Further, the upper limit reference value of the equation (1) is Ll-
The reason for being (100 μm × 2) is that the substrate or coating thickness as the magnetic bodies 4 and 5 on both sides of the chip body 10 is required to be 100 μm or more, respectively. Productivity, in the case of magnetic coating it is necessary to ensure the magnetic properties). For example, L
When 1 = 1 mm, L1- (100 μm × 2) = 800 μ
m, and the equation (1) is 800 μm ≧ t1 ≧ 100 μm.

According to the first embodiment, the ends of the coil conductors 11 and 12 also serve as external electrodes, there is no connecting portion between the coil conductor and the external electrodes, and the quality is excellent and the number of steps is large. The chip-type common mode choke coil is inexpensive and can be easily manufactured. Also, each coil conductor 1
By forming the portions other than the end portions of the external electrodes 1 and 12 which are to be external electrodes in a linear shape, the capacitance between the coil conductor portions is reduced, the resonance frequency of the common mode impedance is increased, and good high-speed transmission characteristics can be obtained. .

FIGS. 3 and 4 show a second embodiment of the present invention in which a closed magnetic circuit structure is provided. In this case, the main configuration and manufacturing procedure are the same as in the first embodiment described above. The difference is that the magnetic material 7 is filled in the outer periphery (upper and lower sides in the illustrated example) of the coil forming portion provided with the first and second coil conductors 11 and 12 on both sides of the insulating layer 1. , 5 form a closed magnetic circuit. Insulating adhesive or sealing member 6 may be provided in the remaining space not filled with magnetic material 7 as in the first embodiment.

According to the second embodiment, a closed magnetic circuit structure is provided in addition to the operation of the first embodiment,
The common mode impedance can be further increased, and the common mode noise suppression effect can be further improved.

FIGS. 5 and 6 show a third embodiment of the present invention, which is another example of the closed magnetic circuit structure. in this case,
The main configuration and manufacturing procedure are the same as those of the first embodiment described above, except that one of the magnetic bodies sandwiching the coil forming portion is formed of the magnetic substrate 8 having the recessed portion 8a, and the other magnetic body is formed. The point is that a closed magnetic circuit structure is formed by abutting and integrating with the substrate 9. If necessary, an insulating adhesive or sealing member 6 may be provided in the space inside the closed magnetic circuit as in the first embodiment.

Even with this structure, the common mode impedance can be increased, that is, the effect of suppressing common mode noise can be further improved.

In the third embodiment described above, the recess is formed only in the magnetic substrate which is one of the magnetic bodies, but the recess may be formed in the magnetic bodies on both sides.

7 and 8 show a fourth embodiment of the present invention. In this case, the shape of the coil conductor of the first embodiment is changed, and the coil conductors 13, 1 forming a pair are changed.
4 is substantially H-shaped as a whole, that is, it has vertical conductor end portions 13a, 13b, 14a, 14b, which are external electrodes for mounting, at both end portions of a lateral straight conductor portion. In this case, the conductor end portions 13a, 13b, 14a, 14b are exposed not only on the side surface and the bottom surface of the chip body 10 but also on the upper surface.
Other configurations are similar to those of the first embodiment described above.

In the fourth embodiment, the conductor end portions 13a, 13b, 14a, 14b serving as the mounting external electrodes are exposed not only on the side surface and the bottom surface of the chip body 10 but also on the upper surface thereof. Since the upper and lower surfaces of the chip body 10 are provided, the electronic component mounting machine side does not need to perform the processing for determining the upper and lower sides of the chip common mode choke coil.

In the above-described embodiments, 1
The element is provided with a pair of coil conductors, but the present invention can be applied to a component in which a plurality of pairs of coil conductors are included in one element. This case is shown in FIG. 9 as a fifth embodiment of the present invention. In the fifth embodiment of FIG. 9, the first
This is a configuration in which a plurality of chip structures 30 having a pair of coil conductors having the structure of the embodiment are integrated via the nonmagnetic layer 2. In FIG. 9, the same or corresponding parts as those of the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted.

According to the fifth embodiment, it is possible to realize a composite component including a plurality of common mode choke coils in one element.

In the fifth embodiment, a plurality of chip structures having the structure of the first embodiment are integrated via the nonmagnetic layer, but the second to fourth embodiments are integrated. A plurality of chip structures having the above structure may be integrated via a non-magnetic layer to form a composite component.

Although the embodiment of the present invention has been described above, it is obvious to those skilled in the art that the present invention is not limited to this and various modifications and changes can be made within the scope of the claims. Ah For example, regarding the manufacturing procedure, in the manufacturing procedure in the above-described first embodiment, the inter-coil insulating layer is started. However, the manufacturing procedure is not limited to this, and the coil conductor 11 is formed on one magnetic body in sequence (insulation A procedure of forming the layer 1, the coil conductor 12, and the magnetic material in this order) may be used.

[0044]

As described above, according to the present invention,
By constructing the external electrodes for mounting by the ends of the paired coil conductors themselves, the connection parts between the coil conductors and external electrodes are eliminated, which is excellent in quality, can be easily manufactured with a small number of steps, and is an inexpensive chip-type common. A mode choke coil can be realized.

When the coil forming portion is sandwiched by magnetic materials to have a closed magnetic circuit structure, a higher common mode impedance can be obtained, and the common mode noise suppressing effect can be further improved.

[Brief description of 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 a perspective view of the same.

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

FIG. 6 is a perspective view of the same.

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

FIG. 8 is a perspective view of the same.

FIG. 9 is a perspective view showing a fifth embodiment of the present invention.

FIG. 10 is an exploded perspective view of a conventional technique.

FIG. 11 is a perspective view of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Insulating layer 2 Non-magnetic layer 4, 5 Magnetic body 7 Magnetic material 8a Recessed portion 8, 9 Magnetic substrate 10 Chip element bodies 11, 12, 13, 14 Coil conductors 11a, 11b, 12a, 12b, 13a, 13b, 1
4a, 14b conductor end 30 chip structure

Claims (7)

[Claims] 1. A coil having a pair of first and second conductors of the same shape formed on the front and back surfaces of an insulating layer, the first and second conductors being sandwiched by a magnetic material from an upper layer, and a pair of only the conductors. It is a structure in which conductors are formed, and both ends of each conductor themselves constitute mounting external electrodes, and the mounting external electrodes are formed such that the formation surface of each conductor is perpendicular to the mounting surface. Characteristic chip type common mode choke coil. 2. The chip type common mode choke coil according to claim 1, wherein a solder connecting layer is formed on the surface of the mounting external electrode by plating or the like. 3. The chip-type common mode choke coil according to claim 1, wherein the insulating layer has a thickness of 100 μm or more. 4. The chip-type common mode choke coil according to claim 1, wherein the insulating layer is an insulating resin sheet made of polyimide, epoxy resin or the like. 5. The chip-type common mode choke coil according to claim 1, wherein the insulating layer is an insulating substrate such as a glass-based epoxy resin substrate. 6. The closed magnetic circuit including the magnetic body forms the first magnetic field.
And a part of the second conductor is covered,
Alternatively, the chip type common mode choke coil as described in 5 above. 7. A plurality of pairs of the first and second conductors of the same shape forming the pair are provided.
5. The chip type common mode choke coil as described in 5 or 6.